CDMS classic documentation - molecules:ism

1h-cyclopent_cd_indene

anonymous@undisclosed.example.com (Anonymous) — Mon, 02 Mar 2026 11:35:31 +0000

2026/02/18 13:29		current
Line 1:		Line 1:
-	===== On the Detection of 1H-Cyclopent[cd]indene, C11H8, in the ISM =====	+	===== On the Detection of 1H-Cyclopent[cd]indene, c-C11H8, in the ISM =====

	R. Fuentetaja, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, P. de Vicente, and J. Cernicharo \\		R. Fuentetaja, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, P. de Vicente, and J. Cernicharo \\
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202558398\|Discovery of 1H-Cyclopent[cd]indene (c-C11H8) in TMC-1 with the QUIJOTE Line Survey: A new Three-Ringed Polycyclic Aromatic Hydrocarbon]]\\		[[https://doi.org/10.1051/0004-6361/202558398\|Discovery of 1H-Cyclopent[cd]indene (c-C11H8) in TMC-1 with the QUIJOTE Line Survey: A new Three-Ringed Polycyclic Aromatic Hydrocarbon]]\\
	//Astron. Astrophys.// 706, Art. No. L10 (2026).\\		//Astron. Astrophys.// 706, Art. No. L10 (2026).\\
-	The molecule was identified through 22 lines, each consisting of an oblated paired of four //a//- and //b//-type transitions with 15 ≤ //J// ≤ 24 and //J// − 5 ≤ //K<sub>c</sub>// ≤ //J//. The rotational temperature was assumed as 9 K. The derived column density is about a factor of 2.7 lower than that of indene and about a factor of 4.7 lower than that of phenalene.\\	+	The molecule was identified through 22 //R//-branch lines, each consisting of an oblated paired of four //a//- and //b//-type transitions with 15 ≤ //J// ≤ 24 and //J// − 5 ≤ //K<sub>c</sub>// ≤ //J//. The rotational temperature was assumed as 9 K. The derived column density is about a factor of 2.7 lower than that of indene and about a factor of 4.7 lower than that of phenalene.\\
	\\		\\

2_new_mols

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Feb 2019 21:38:39 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Ethyl Formate and n-Propyl Cyanide toward Sagittarius B2(N) =====
	+
	+	Two among the largest molecules, ethyl formate, C<sub>2</sub>H<sub>5</sub>OCHO, and //n//-propyl cyanide, //n//-C<sub>3</sub>H<sub>7</sub>CN, have been detected in the famous massive star-forming region Sagittarius B2(N) in the course of a molecular line survey in the 3mm frequency domain with additional observations at 2 and 1 mm carried out with the IRAM 30m radiotelescope:\\
	+	A. Belloche, R. T. Garrod, H. S. P. Müller, K. M. Menten, C. Comito, and P. Schilke,\\
	+	[[http://dx.doi.org/10.1051/0004-6361/200811550\|Increased Complexity in Interstellar Chemistry: Detection and Chemical Modeling of Ethyl Formate and //n//-Propyl Cyanide in Sagittarius B2(N)]]\\
	+	//Astron. Astrophys.// 499, (2009) 215–232.\\
	+
	+
	+	These are the second and third molecules after [[http://www.astro.uni-koeln.de/site/vorhersagen/molecules/ism/AAN.html\|aminoacetonitrile]] to be detected newly within this molecular line survey.\\
	+	Ethyl formate is the second formate to be detected in the ISM after [[http://www.astro.uni-koeln.de/site/vorhersagen/molecules/ism/Methylformiat.html\|methyl formate]]. The parent species formic acid, [[http://www.astro.uni-koeln.de/site/vorhersagen/molecules/ism/Formic_Acid.html\|HCOOH]], has also been detected. The isomeric methyl acetate, CH<sub>3</sub>OC(O)CH<sub>3</sub>, has not yet been detected – in part because of very limited laboratory data.\\
	+	//n//-Propyl cyanide is the third member after methyl cyanide, CH<sub>3</sub>CN, and ethyl cyanide, [[http://www.astro.uni-koeln.de/site/vorhersagen/molecules/ism/EtCN.html\|C<sub>2</sub>H<sub>5</sub>CN]].
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 04, 2009
	+
	+
	+	----
	+

2-hpa

anonymous@undisclosed.example.com (Anonymous) — Wed, 04 Mar 2026 10:15:25 +0000

2026/03/04 11:00		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202558316\|Expanding the C3H6O2 Isomeric Interstellar Inventory: Discovery of Lactaldehyde and Methoxyacetaldehyde in G+0.693−0.027]]\\		[[https://doi.org/10.1051/0004-6361/202558316\|Expanding the C3H6O2 Isomeric Interstellar Inventory: Discovery of Lactaldehyde and Methoxyacetaldehyde in G+0.693−0.027]]\\
	//Astron. Astrophys.// 706, (2026) Art. No. A316.\\		//Astron. Astrophys.// 706, (2026) Art. No. A316.\\
-	2-Hydroxypropanal, also known as lactaldehyde, was detected in the course of a molecular line survey of this cold, shocked molecular cloud near Sagittarius B2 and in the Galactic center region. Three transitions with good signasl-to-noise ratio (S/N) and one with modest S/N between 32 and 138 GHz were unblened, three further transitions slightly blended. \\	+	2-Hydroxypropanal, also known as lactaldehyde, was detected in the course of a molecular line survey of this cold, shocked molecular cloud near Sagittarius B2 and in the Galactic center region. Three transitions with good signal-to-noise ratio (S/N) and one with modest S/N between 32 and 138 GHz were unblended, three further transitions slightly blended. The authors provide column density raios of the C<sub>3</sub>H<sub>6</sub>O<sub>2</sub> isomers.\\
	\\		\\

3b

anonymous@undisclosed.example.com (Anonymous) — Mon, 12 Apr 2021 15:14:06 +0000

2021/04/12 17:06		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/aba632\|Early Science from GOTHAM: Project Overview, Methods, and the Detection of Interstellar Propargyl Cyanide (HCCCH<sub>2</sub>CN) in TMC-1]]\\		[[https://doi.org/10.3847/2041-8213/aba632\|Early Science from GOTHAM: Project Overview, Methods, and the Detection of Interstellar Propargyl Cyanide (HCCCH<sub>2</sub>CN) in TMC-1]]\\
	//Astrophys. J. Lett.// 900, Art. No. L10 (2020).\\		//Astrophys. J. Lett.// 900, Art. No. L10 (2020).\\
-	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting of the 4<sub>1,3</sub>−3<sub>1,2</sub>, 5<sub>1,5</sub>−4<sub>1,4</sub>, 5<sub>0,5</sub>−4<sub>0,4</sub>, and 5<sub>1,4</sub>−4<sub>1,3</sub> transitions near 22.6, 26.6, 27.3, and 28.2 GHz, respectively, at the expense of noise levels of about the same level as the individual lines. The analysis was improved by employing a stacking technique.	+	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting of the 4<sub>1,3</sub>−3<sub>1,2</sub>, 5<sub>1,5</sub>−4<sub>1,4</sub>, 5<sub>0,5</sub>−4<sub>0,4</sub>, and 5<sub>1,4</sub>−4<sub>1,3</sub> transitions near 22.6, 26.6, 27.3, and 28.2 GHz, respectively, at the expense of noise levels of about the same level as the individual lines. The analysis was improved by employing a stacking technique.\\
		+
		+
		+	N. Marcelino, B. Tercero, M. Agúndez and J. Cernicharo\\
		+	reported shortly thereafter on\\
		+	[[https://doi.org/10.1051/0004-6361/202040177\|A study of C<sub>4</sub>H<sub>3</sub>N isomers in TMC-1: Line by line detection of HCCCH<sub>2</sub>CN in TMC-1]]\\
		+	//Astron. Astrophys.// 646, Art. No. L9 (2021).\\
		+	Several //a//-type transitions and even some weak //b//-type transitions were detected in the course of their molecular line survey carried out with the Yebes 40 m radio-telescope.\\

aan

anonymous@undisclosed.example.com (Anonymous) — Fri, 26 Apr 2019 13:35:46 +0000

2019/04/26 15:34		current
Line 8:		Line 8:
	//Astron. Astrophys.// 492, (2008) 769–773.		//Astron. Astrophys.// 492, (2008) 769–773.

-	A [[http://www.mpg.de/english/illustrationsDocumentation/documentation/pressReleases/2008/pressRelease20080325/index.html\|press release]] is also available, not only in English, but also in [[https://www.mpg.de/554371/pressemitteilung20080325\|German]].	+	A [[https://www.mpg.de/567495/pressRelease20080325\|press release]] is also available, not only in English, but also in [[https://www.mpg.de/554371/pressemitteilung20080325\|German]].

acetamid

anonymous@undisclosed.example.com (Anonymous) — Fri, 06 Nov 2020 11:25:11 +0000

2019/04/26 14:50		current
Line 16:		Line 16:
	A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito\\		A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito\\
	investigated\\		investigated\\
-	[[http://dx.doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\	+	[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\
	//Astron. Astrophys.// 559, Art. No. A47 (2013).\\		//Astron. Astrophys.// 559, Art. No. A47 (2013).\\
-	They observed several transitions in the two lowest excited torsional state.	+	They observed several transitions in the two lowest excited torsional state.\\

		+	N. F. W. Ligterink, S. J. El-Abd, C. L. Brogan, T. R. Hunter, A. J. Remijan, R. T. Garrod, and B. M. McGuire\\
		+	investigated\\
		+	[[https://doi.org/10.3847/1538-4357/abad38\|The Family of Amide Molecules toward NGC 6334I]]\\
		+	//Astrophys. J.// 901, Art. No. 37 (2020).\\
		+	They detected the molecule toward the position MM1-i among others.\\

-	----

-	Contributor(s): H. S. P. Müller; 4, 2006; 12, 2011; 04, 2019	+	----

		+	Contributor(s): H. S. P. Müller; 4, 2006; 12, 2011; 04, 2019; 10, 2020

	----		----

aceton

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:52:25 +0000

alo

anonymous@undisclosed.example.com (Anonymous) — Thu, 10 Dec 2020 10:37:55 +0000

ammoniak

anonymous@undisclosed.example.com (Anonymous) — Fri, 06 Feb 2026 10:18:38 +0000

2026/02/06 11:01		current
Line 19:		Line 19:
	\\		\\

-	S. Hüttemeister, T. L. Wilson, R. Mauersberger, C. Lemme, G. Dahmen, and C. Henkel\\	+	T. L. Wilson, C. Henkel, and S. Hüttemeister, G. Dahmen, A. Linhart, C. Lemme, and J. Schmidt-Burgk\\
-	carried out\\	+	reported on\\
-	[[https://ui.adsabs.harvard.edu/abs/1995A%26A...294..667H\|A Multilevel Study of Ammonia in Star-Forming Regions. VI. The Envelope of Sagittarius B2.]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1993A%26A...276L..29W\|Hot Ammonia Emission: Kinetic Temperature Gradients in Orion-KL]]\\
-	//Astron. Astrophys.// **294, 667−676 (1995**).\\	+	//Astron. Astrophys.// **276, L29−L32 (1993**).\\
-	The MPIfR 100 m Effelsberg telescope was employed for observations of ammonia inversion transitions with 8 ≤ //J// = //K// ≤ 14 toward Sgr B2(M) and Sgr B2(N).\\	+	The MPIfR 100 m Effelsberg telescope was employed for observations of ammonia inversion transitions with 10 ≤ //J// = //K// ≤ 14.\\
	\\		\\

Line 37:		Line 37:
	[[https://ui.adsabs.harvard.edu/abs/1988A%26A...205..235M\|Vibrationally Excited Ammonia toward Orion-KL]]\\		[[https://ui.adsabs.harvard.edu/abs/1988A%26A...205..235M\|Vibrationally Excited Ammonia toward Orion-KL]]\\
	//Astron. Astrophys.// 205, 235–242 (1988).\\		//Astron. Astrophys.// 205, 235–242 (1988).\\
		+	The IRAM 30 m dish was used for observations near 140.1 GHz.

	---		---

ammonium

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:20:11 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Ammonium, NH4+, in the ISM =====
	+
	+	The ammonium cation, NH<sub>4</sub><sup>+</sup>, is among the most stable gas phase cations because of the very large proton affinity of ammonia, NH<sub>3</sub>. However, NH<sub>4</sub><sup>+</sup> itself can not be detected by radio astronomy because the spherical symmetry precludes the molecule from having a permanent electric dipole moment. In contrast, the separation of the charge from the center of mass causes the mono-deuterated isotopolog to have a comparatively large dipole moment of about 0.26 D.
	+
	+	J. Cernicharo, B. Tercero, A. Fuente, J. L. Domenech, M. Cueto, E. Carrasco, V. J. Herrero, I. Tanarro, N. Marcelino, E. Roueff, M. Gerin, and J. C. Pearson\\
	+	reported on\\
	+	[[https://doi.org/10.1088/2041-8205/771/1/L10\|Detection of the Ammonium Ion in Space]]\\
	+	//Astrophys. J.// 771, Art. No. L10 (2013).\\
	+	The //J<sub>K</sub>// = 1<sub>0</sub> – 0<sub>0</sub> transition of NH<sub>3</sub>D<sup>+</sup> at a derived rest frequency of 262816.73 (10) MHz was detected with the IRAM 30 m telescope. The line was detected with good signal-to-noise ratio in the star-forming region Orion-IRc2 in the course of a molecular line survey and just barely in the dark cloud B1-bS in subsequent dedicated observations. The detection is probably fairly secure even if the laboratory rest frequency was only determined with infared accuracy, and even though Orion-IRc2 is rather line rich.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller 06, 2013
	+
	+	----
	+

arh-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:20:39 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Argonium, ArH+, in the Interstellar Medium =====
	+
	+	The //J// = 1 – 0 and 2 – 1 transitions of <sup>36</sup>ArH<sup>+</sup> were detected in emission with the SPIRE instrument on the //Herschel// satellite toward the Crab Nebula supernova remnant, also known as M 1, by:\\
	+	M. J. Barlow, B. M. Swinyard, P. J. Owen, J. Cernicharo, H. L. Gomez, R. J. Ivison, O. Krause, T. L. Lim, M. Matsuura, S. Miller, G. Olofsson, and E. T. Polehampton,\\
	+	[[https://doi.org/10.1126/science.1243582\|Detection of a Noble Gas Molecular Ion, <sup>36</sup>ArH<sup>+</sup>, in the Crab Nebula]]\\
	+	//Science// 342, (2013) 1343.\\
	+	<sup>40</sup>Ar is the most abundant isotope on Earth, but it is almost exclusively formed in the radioactive decay of <sup>40</sup>K. Interestingly, the only other feature seen clearly in the entire spectrum was the strongest fine structure component of OH<sup>+</sup>, there is also a hint of the next weaker FS component.
	+
	+	More recently,\\
	+	P. Schilke, D. A. Neufeld, H. S. P. Müller, C. Comito, E. A. Bergin, D. C. Lis, M. Gerin, J. H. Black, M. Wolfire, N. Indriolo, J. C. Pearson, K. M. Menten, B. Winkel, Á. Sánchez-Monge, T. Möller, B. Godard, and E. Falgarone,\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/201423727\|Ubiquitous argonium (ArH<sup>+</sup>) in the diffuse interstellar medium: A molecular tracer of almost purely atomic gas]]\\
	+	//Astron. Astrophys.// 566 (2014), Art. No. A29.\\
	+	The 1 – 0 transition was observed in absorprtion with HIFI on board of the //Herschel// satellite toward numerous prominent continuum sources, first, and most notably, toward Sagittarius B2(M), then Sgr B2(N), and later also toward W51e, W49N, W31C, and G34.26+0.15. Interestingly, the molecule displays absorption at velocities associated with diffuse molecular clouds on the line of sight toward the contiunuum sources, but is conspicuously absent (at least in most cases) at the velocity of the corresponding continuum source itself. Model calculations indicate that ArH<sup>+</sup> resides mostly in very atomic diffuse molecular clouds with a molecular fraction of around 0.001 to 0.0001 or less. It is thus a very good tracer of such interstellar material. Moreover, it is also a good indicator of the cosmic ray ionization rate in addition to or instead of OH<sup>+</sup>, H<sub>2</sub>O<sup>+</sup>, or H<sub>3</sub><sup>+</sup>.\\
	+	\\
	+	The authors also detected the 1 – 0 transition of <sup>38</sup>ArH<sup>+</sup> toward Sgr B2(M). The <sup>36</sup>Ar/<sup>38</sup>Ar is compatible within error bars with the the local ISM value of about 5.5.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2013; 06, 2014
	+
	+	----
	+

bd-e1cn

anonymous@undisclosed.example.com (Anonymous) — Tue, 20 May 2025 11:02:07 +0000

2023/07/27 13:34		current
Line 6:		Line 6:
	//Astrophys. J.// 948, Art. No. 133 (2023).\\		//Astrophys. J.// 948, Art. No. 133 (2023).\\
	The identification was made by stacking data from the GBT line survey that covers ~24.9 GHZ of the 7.9 to 36.4 GHz region. The //E// form of 1-cyano-1,3-butadiene is less abundant than the two detected cyanocyclopentadiene isomers by factors of a few, somewhat depending on the sources of the column densities of the cyclic species.\\		The identification was made by stacking data from the GBT line survey that covers ~24.9 GHZ of the 7.9 to 36.4 GHz region. The //E// form of 1-cyano-1,3-butadiene is less abundant than the two detected cyanocyclopentadiene isomers by factors of a few, somewhat depending on the sources of the column densities of the cyclic species.\\
		+	\\
		+
		+	M. Agúndez, C. Cabezas, N. Marcelino, B. Tercero, R. Fuentetaja, P. de Vicente, and J. Cernicharo\\
		+	cast serious doubt on this detection in their study\\
		+	[[https://doi.org/10.1051/0004-6361/202554343\|A Search for the Three Isomers of Cyano-1,3-butadiene in TMC-1: Implications for Bottom-up Routes Involving 1,3-Butadiene]]\\
		+	//Astron. Astrophys.// 697, Art. No. A82 (2025).\\
		+	They use their QUIJOTE line survey between 31.0 and 50.3 GHz to search for //E//-1-, //Z//-1-, and 2-cyano-1,3-butadiene. None of the isomers was detected. Moreover, the upper limit for the column density of //E//-1-cyano-1,3-butadiene is a factor of three lower than the one reported in the study above. Therefore, the molecule is considered as undetected for now. An additional outcome of this study is that the role of 1,3-butadiene in the bottom-up formation of PAHs is likely smaller than thought thus far.\\
	\\		\\

	----		----

-	Contributor(s): H. S. P. Müller; 07, 2023	+	Contributor(s): H. S. P. Müller; 07, 2023; 05, 2025

	----		----

benzol

anonymous@undisclosed.example.com (Anonymous) — Wed, 24 Apr 2019 13:18:49 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Benzene in the Circumstellar Envelopes =====
	+
	+	J. Cernicharo, A. M. Heras, A. G. G. M. Tielens, J. R. Pardo, F. Herpin, M. Guélin, and L. B. F. M. Waters,\\
	+	[[https://doi.org/10.1086/318871\|//Infrared Space Observatory's// Discovery of C<sub>4</sub>H<sub>2</sub>, C<sub>6</sub>H<sub>2</sub>, and Benzene in CRL 618]]\\
	+	//Astrophys. J.// 546, L123–L126 (2001);\\
	+	report the detection of the ν<sub>4</sub> band of benzene with an origin at 674.0 cm<sup>–1</sup> (or 14.84 μm) employing mid-infrared spectroscopy. The band is clearly observed, but not particularly strong. Unfortunately, possible rotational substructure, including that from hot-band, may be present, but is near the noise limit as pointed out by the authors. The derived abundances seem plausible. Moreover, the PAH hypothesis, which most astronomers accept with little caution, if any, requires the presence of benzene in such environments, as probably do the recently reported rather secure [[molecules:ism:fullerene\|detections of C<sub>60</sub> and C<sub>70</sub>]]. Finally, there does not seem to be any alternative assignment for this feature. Overall, one can probably view the detection of benzene as, at least, fairly secure, but a small degree of caution may be useful.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2003; modified 1, 2011
	+
	+
	+	----
	+

benzyne

anonymous@undisclosed.example.com (Anonymous) — Tue, 24 Aug 2021 11:03:17 +0000

2021/08/24 12:50		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202141660\|Discovery of Benzyne, //o//-C<sub>6</sub>H<sub>4</sub>, in TMC-1 with the QUIJOTE Line Survey]]\\		[[https://doi.org/10.1051/0004-6361/202141660\|Discovery of Benzyne, //o//-C<sub>6</sub>H<sub>4</sub>, in TMC-1 with the QUIJOTE Line Survey]]\\
	//Astron. Astrophys.// 652, Art. No. L9 (2021).\\		//Astron. Astrophys.// 652, Art. No. L9 (2021).\\
-	The //ortho// isomer of benzyne, //c//-C<sub>6</sub>H<sub>4</sub>,	+	The //ortho// isomer of benzyne, //c//-C<sub>6</sub>H<sub>4</sub>, was identified through nine //b//-type transitions with 2 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 2 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. Six of these lines appear to be unblended or only slightly blended. A value of //T//<sub>rot</sub> ≈ 7 K was derived. The column density of //ortho//-benzyne is much lower than that of, e.g., cyclopentadiene and indene and similar to that of ethynylcylopropenylidene.\\
		+
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 08, 2021
		+
		+	----

butadiynyliminomethylium

anonymous@undisclosed.example.com (Anonymous) — Tue, 27 Dec 2022 13:14:11 +0000

2022/03/25 11:18		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202039251\|Tentative Detection of HC<sub>5</sub>NH<sup>+</sup> in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202039251\|Tentative Detection of HC<sub>5</sub>NH<sup>+</sup> in TMC-1]]\\
	//Astron Astrophys.// 643, Art. No. L6 (2020).\\		//Astron Astrophys.// 643, Art. No. L6 (2020).\\
-	Seven transitions, from //J"// = 12 to 18 between about 33.7 and 49.2 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Quantum-chemical calculations yielded HC<sub>5</sub>NH<sup>+</sup> as the most likely carrier of these lines. The abundance ratio of HC<sub>5</sub>N to HC<sub>5</sub>NH<sup>+</sup> is ~240, very similar to that of HC<sub>3</sub>N to HC<sub>3</sub>NH<sup>+</sup>, which can be seen as additional support for the identification. The "tentative" in the title refers to the identification of the carrier, but that may be viewed as almost definitive.\\	+	Seven transitions, from //J"// = 12 to 18 between about 33.7 and 49.2 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Quantum-chemical calculations yielded HC<sub>5</sub>NH<sup>+</sup> as the most likely carrier of these lines. The abundance ratio of HC<sub>5</sub>N to HC<sub>5</sub>NH<sup>+</sup> is ~240, very similar to that of HC<sub>3</sub>N to HC<sub>3</sub>NH<sup>+</sup>, which can be seen as additional support for the identification. The "tentative" in the title refers to the identification of the carrier. The spectroscopic parameters are very similar to those of [[molecules:ism:NC4NH-plus\|NC]]<sub>4</sub>NH<sup>+</sup>. But with the detection of the latter, this has been settled.\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller 10, 2020; 03, 2022	+	Contributor(s): H. S. P. Müller 10, 2020; 03, 2022; 12, 2022

	----		----

butin

anonymous@undisclosed.example.com (Anonymous) — Wed, 12 Jun 2024 15:08:57 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Butyne in the ISM =====
	+
	+	J. Cernicharo, B. Tercero, M. Agúndez, C. Cabezas, R. Fuentetaja, N. Marcelino and P. de Vicente\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/202449531\|CN and CCH Derivatives of Ethylene and Ethane: Confirmation of the Detection of CH<sub>3</sub>CH<sub>2</sub>CCH in TMC-1]]\\
	+	//Astron. Astrophys.// 686, Art. No. A139 (2024).\\
	+	1-Butyne, aka ethylacetylene, was identified through 9 unblended or slightly blended //a//-type transitions with 3 ≤ //J// ≤ 5 and //K<sub>a</sub>// ≤ 2 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 33.6 and 44.3 GHz. A value of //T//<sub>rot</sub> ≈ 9 K was derived. The column density of 1-butnyne is about a factor of 15 lower than that of butenyne.\\
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2024
	+
	+	----

c_no

anonymous@undisclosed.example.com (Anonymous) — Mon, 20 Dec 2021 13:53:17 +0000

2021/12/20 14:42		current
Line 33:		Line 33:

	The molecules was also detected in the circumstellar envelope of the C-rich AGB star CW Leonis by\\		The molecules was also detected in the circumstellar envelope of the C-rich AGB star CW Leonis by\\
		+	E. D. Tenenbaum, A. J. Apponi, L. M. Ziurys, M. Agúndez, J. Cernicharo, J. R. Pardo, and M. Guélin\\
		+	[[https://doi.org/10.1086/508166\|Detection of C<sub>3</sub>O in IRC +10216: Oxygen-Carbon Chain Chemistry in the Outer Envelope]]\\
		+	//Astrophys. J. // 649, L17–L20 (2006).\\
		+	Observations were carried out at 3 and 2 mm using the ARO 12 m dish and a 3 mm using the IRAM 30 m telescope.\\
		+
		+	M. E. Palumbo, P. Leto, C. Siringo, and C. Trigilio\\
		+	reported on the\\
		+	[[https://doi.org/10.1086/591017\|Detection of C<sub>3</sub>O in the Low-Mass Protostar Elias 18]]\\
		+	//Astrophys. J. // 297, 302–308 (1985).\\
		+	The Noto 32 m dish was employed to serach for the //J// = 4 − 3 transition near 38.5 GHz.\\

	==== Oxopentatetraenylidene, C<sub>5</sub>O ====		==== Oxopentatetraenylidene, C<sub>5</sub>O ====

c-c3c2h

anonymous@undisclosed.example.com (Anonymous) — Tue, 19 Jul 2022 08:39:04 +0000

2022/07/19 10:29		current
Line 1:		Line 1:
-	===== Detection of Ethynylcyclopropynylidyne, c-C3H2H, in the ISM =====	+	===== Detection of Ethynylcyclopropynylidyne, c-C3C2H, in the ISM =====

	C. Cabezas, M. Agúndez, R. Fuentetaja, Y. Endo, N. Marcelino, B. Tercero, J. R. Pardo, P. de Vicente, and J. Cernicharo\\		C. Cabezas, M. Agúndez, R. Fuentetaja, Y. Endo, N. Marcelino, B. Tercero, J. R. Pardo, P. de Vicente, and J. Cernicharo\\
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202244063\|Discovery of the Cyclic C<sub>5</sub>H Radical in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202244063\|Discovery of the Cyclic C<sub>5</sub>H Radical in TMC-1]]\\
	//Astron Astrophys.// 663, Art. No. L2 (2022).\\		//Astron Astrophys.// 663, Art. No. L2 (2022).\\
-	Transitions with //J"// = 4 to 6 and //K<sub>a</sub>// = 1 between 33.0 and 46.4 GHz were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Fine structure splitting was resolved throughout, hyperfine splitting in many cases. The C<sub>3</sub>S to HC<sub>3</sub>S<sup>+</sup> ratio is 65 ± 20, and the HC<sub>3</sub>O<sup>+</sup> to HC<sub>3</sub>S<sup>+</sup> ratio is 1.0 ± 0.5. The C<sub>3</sub>O to C<sub>3</sub>S ratio, in contrast, is ~0.11.	+	Transitions with //J"// = 4 to 6 and //K<sub>a</sub>// = 1 between 33.0 and 46.4 GHz were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Fine structure splitting was resolved throughout, hyperfine splitting in many cases. The rotational temperature was determined as 6.0 ± 0.5 K. The //c//-C<sub>5</sub>H to //l//-C<sub>5</sub>H ratio is about 0.07, very different from the //c//-C<sub>3</sub>H to //l//-C<sub>3</sub>H ratio of ~5.5.

c-c3h

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:35:47 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Cyclopropanediylidenyl, c-C3H, in Space =====
	+
	+	C<sub>3</sub>H exists in two isomeric forms, a linear one and a cyclic one. The latter is considerably higher in energy. Still, both seem to be equally abundant in cold dark clouds. The cyclic isomer has three CC bonds of essentially equal lengths which correspond to a bond order of 1.5. The molecule can be viewed best as derived from cyclopropane by removing 2 × 2 plus one H atoms, yielding cyclopropanediylidenyl as the probably most appropriate name. //c//-C<sub>3</sub>H was detected first in the dense cold molecular cloud TMC-1 by\\
	+	S. Yamamoto, S. Saito, M. Ohishi, H. Suzuki, S.-I. Ishikawa, N. Kaifu, and A. Murakami,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987ApJ...322L..55Y\|Laboratory and Astronomical Detection of the Cyclic C<sub>3</sub>H Radical]],\\
	+	//Astrophys. J.// 322, L55–L58 (1987).\\
	+	Two hyperfine components each were detected for the two fine structure components of the 2<sub>12</sub> – 1<sub>11</sub> transition near 91.5 and 91.7 GHZ, respectively, employing the Nobeyama 45 m telescope.
	+
	+	Two hfs components of the 1<sub>10</sub> – 1<sub>11</sub> transition near 14.9 GHz were detected with the 43 m NRAO telecope in several other dense dark clouds by\\
	+	J. G. Mangum and A. Wooten,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1990A%26A...239..319M\|Observations of the Cyclic C<sub>3</sub>H Radical in the Interstellar Medium]],\\
	+	//Astron. Astrophys.// 239, 319–325 (1990).
	+
	+	The radical was also observed in three translucent molecular clouds CB 17, CB 24, and CB 228 by\\
	+	B. E. Turner, E. Herbst, and R. Terzieva,\\
	+	[[https://doi.org/10.1086/313301\|The Physics and Chemistry of Small Translucent Molecular Clouds. XIII. The Basic Hydrocarbon Chemistry]],\\
	+	//Astrophys. J. Suppl. Ser.// 126, 427–460 (2000).
	+
	+	The presence of //c//-C<sub>3</sub>H in the circumstellar envelopes of carbon rich late type stars was also established. E.g. CW Leo by\\
	+	J.Cernicharo, M. Guélin, and C. Kahane,\\
	+	[[https://doi.org/10.1051/aas:2000147\|A λ 2 mm Molecular Line Survey of the C-star Envelope IRC+10216]],\\
	+	//Astron. Astrophys. Suppl. Ser.// 142, 181–215 (2000).\\
	+	and LL Peg by\\
	+	Y. Zhang, S. Kwok, and J.-I. Nakashima,\\
	+	[[https://doi.org/10.1088/0004-637X/700/2/1262\|A Molecular Line Survey of the Extreme Carbon Star CRL 3068 at Millimeter Wavelengths]],\\
	+	//Astrophys. J.// 700, 1262–1281 (2009).
	+
	+	H. S. Liszt, J. Pety, M. Gerin, and R. Lucas,\\
	+	detected with the IRAM 30 m telescope\\
	+	[[https://doi.org/10.1051/0004-6361/201323320\|HCO, //c//-C<sub>3</sub>H and CF<sup>+</sup>: three new molecules in diffuse, translucent and “spiral-arm” clouds]]\\
	+	//Astron. Astrophys.// 564, Art. No. A64 (2014).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 09, 2011; 10, 2017
	+
	+	----
	+

c-c3h2

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:01:27 +0000

c-c5h5cch

anonymous@undisclosed.example.com (Anonymous) — Fri, 21 Oct 2022 12:03:31 +0000

2021/12/03 16:34		current
Line 1:		Line 1:
	===== On the Detection of Ethynylcyclopentadienes in the ISM =====		===== On the Detection of Ethynylcyclopentadienes in the ISM =====

-	J. Cernicharo, M. Agúndez, R. I. Kaiser, C. Cabezas, B. Tercero, N. Marcelino, J. R. Pardo, and P. de Vicente\\	+	J. Cernicharo, M. Agúndez, R. I. Kaiser, C. Cabezas, B. Tercero, N. Marcelino, J. R. Pardo, and P. de Vicente\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.1051/0004-6361/202142226\|Discovery of two isomers of ethynyl cyclopentadiene in TMC-1: Abundances of CCH and CN derivatives of hydrocarbon cycles]]\\		[[https://doi.org/10.1051/0004-6361/202142226\|Discovery of two isomers of ethynyl cyclopentadiene in TMC-1: Abundances of CCH and CN derivatives of hydrocarbon cycles]]\\
	//Astron. Astrophys.// 655, Art. No. L1 (2021).\\		//Astron. Astrophys.// 655, Art. No. L1 (2021).\\
	Both low-lying isomers, 1- and 2-ethynylcyclopentadiene, were indentified in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. 11 and 21 //a//-type transitions respectively with 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 3 were reported to be unblended or only slightly blended. The lines have modest to reasonable signal-to-noise ratios. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived. The 2-isomer is about 1.4 times more abundant than the 1-isomer and about a factor of 6 less abundant than cyclopentadiene. The authors also rederive columndensities for the isoelectronic cyanocyclopentadienes. They are less abundant than their respective ethynyl relatives by factors of 4.5 and 15 for the 1- and 2-isomers, respectively. Phenylethyne was identified tentatively; it would be at most only a factor of 2 more abundant than phenyl cyanide, aka benzonitrile.\\		Both low-lying isomers, 1- and 2-ethynylcyclopentadiene, were indentified in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. 11 and 21 //a//-type transitions respectively with 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 3 were reported to be unblended or only slightly blended. The lines have modest to reasonable signal-to-noise ratios. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived. The 2-isomer is about 1.4 times more abundant than the 1-isomer and about a factor of 6 less abundant than cyclopentadiene. The authors also rederive columndensities for the isoelectronic cyanocyclopentadienes. They are less abundant than their respective ethynyl relatives by factors of 4.5 and 15 for the 1- and 2-isomers, respectively. Phenylethyne was identified tentatively; it would be at most only a factor of 2 more abundant than phenyl cyanide, aka benzonitrile.\\
		+	\\

	----		----

c-c6h6s

anonymous@undisclosed.example.com (Anonymous) — Wed, 08 Apr 2026 09:08:09 +0000

2026/04/08 11:03		current
Line 5:		Line 5:
	[[https://doi.org/10.1038/s41550-025-02749-7\|A Detection of Sulfur-Bearing Cyclic Hydrocarbons in Space]]\\		[[https://doi.org/10.1038/s41550-025-02749-7\|A Detection of Sulfur-Bearing Cyclic Hydrocarbons in Space]]\\
	//Nat. Astron.// 10, 401 (2026).\\		//Nat. Astron.// 10, 401 (2026).\\
-	The molecule was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m telecope. The //a//-type transitions cover 31 to 49 GHz with 10 ≤ //J// ≤ 19 and //K<sub>a</sub>// ≤ 7. Some lines are unblended, slightly blended, or the peak of the line is at most slightly blended. Some further lines are blended more substantially. The glycolaldehyde/glycolamide ratio is ∼15, while the ethanol/ethanolamine ratio is ∼40.\\	+	2,5-Cyclohexadienthione was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m telecope. The //a//-type transitions cover 31 to 49 GHz with 10 ≤ //J// ≤ 19 and //K<sub>a</sub>// ≤ 7. Some lines are unblended, slightly blended, or the peak of the line is at most slightly blended. //T//<sub>rot</sub> ≈ 12.5 K was derived from a rotation diagram. 2,4-Cyclohexadienthione was not detected, its abundance is at least a factor of 2 lower than 2,5-cyclohexadienthione.\\
	\\		\\

c2_3s

anonymous@undisclosed.example.com (Anonymous) — Mon, 20 Dec 2021 11:48:02 +0000

c2h

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:18:52 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Ethynyl, C2H, in Space =====
	+
	+	The ethynyl radical in its <sup>2</sup>Σ ground vibrational state was detected with the NRAO 11 m telescope in the four stronger of the six hyperfine components of the //N// = 1 – 0 rotational transitions near 87.4 GHz by\\
	+	K. D. Tucker, M. L. Kutner, and P. Thaddeus,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1974ApJ...193L.115T\|The Ethynyl Radical C<sub>2</sub>H – A New Interstellar Molecule]],\\
	+	//Astrophys. J.// 193 L115–L119 (1974)\\
	+	before it was actually detected in the laboratory. The identification was based on hyperfine parameters obtained from electron-spin resonance measurements of ethynyl isolated in argon matrices. The molecule is rather ubiquitous as it has been detected in several star-forming regions such as W3, Orion A, Sgr B2, Sgr A, of which several include photon-dominated regions (PDRs), most notably M17 SW. It has also been detected in the circumstellar envelope of the carbon-rich late-type star CW Leo, also known as IRC +10216.
	+
	+	A. Wootten, E. P. Bozyan, D. P. Garrett, R. B. Loren, and R. L. Snell reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1980ApJ...239..844W\|Detection of C<sub>2</sub>H in Cold Dark Clouds]],\\
	+	//Astrophys. J.// 239 944–854 (1980).
	+
	+	The radical was also observed in the diffuse medium by:\\
	+	L.-Å. Nyman,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1984A%26A...141..323N\|Detection of CS and C<sub>2</sub>H in Absorption]],\\
	+	//Astron. Astrophys.// 141 323–327 (1984).
	+
	+	C<sub>2</sub>D was detected near 216.4 GHz with the 5 m MWO telescope toward Orion KL by:\\
	+	F. Combes, F. Boulanger, P. J. Encrenaz, M. Gerin, M. Bogey, C. Demuynck, J. L. Destomb,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1985A%26A...147L..25C\|Detection of Interstellar CCD]],\\
	+	//Astron. Astrophys.// 147 L25–L26 (1985).
	+
	+	The detection of the <sup>13</sup>C isotopic species was reported in:\\
	+	A. H. Saleck, R. Simon, G. Winnewisser, J. G. A. Wouterloot,\\
	+	[[https://doi.org/10.1139/p94-098\|Detection of Interstellar <sup>13</sup>CCH and C<sup>13</sup>CH]],\\
	+	//Can. J. Phys.// 72 747–754 (1994).
	+
	+	Three out of four observable fine structure components of the //N// = 3 – 2 rotational transition of vibrationally excited C<sub>2</sub>H were reportedly not overlapped:\\
	+	E. D. Tenenbaum, J. L. Dodd, S. N. Milam, N. J. Woolf, and L. M. Ziurys,\\
	+	[[https://doi.org/10.1088/2041-8205/720/1/L102\|Comparative Spectra of Oxygen-rich Versus Carbon-rich Circumstellar Shells: VY Canis Majoris and IRC +10216 at 215-285 GHz]],\\
	+	//Astrophys. J.// 720 L102–L107 (2010).\\
	+	The features were detected in the outer part of the circumstellar envelope of CW Leo; hence, the detection must be facilitated by formation pumping or by IR pumping.
	+
	+	The //A// <sup>2</sup>Π – //X// <sup>2</sup>Σ<sup>+</sup> first excited electronic transition of C<sub>2</sub>H is distributed over at least 5 bands because of vibronic coupling of the //A// with various higher excited vibrational Π states of the ground electronic //X// state. Almost 30 lines belonging to two of the stronger bands were detected with the Mayall telescope near 4011 and 4108 cm<sup>–1</sup> in the outer region of the circumstellar envelope of CW Leo by\\
	+	J. J. Keady and K. H. Hinkle,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1988ApJ...331..539K\|C<sub>2</sub>H in the 2 micron Infrared Spectrum of IRC +10216]],\\
	+	//Astrophys. J.// 331 539–546 (1988).\\
	+	The rotational temperature of 12.5 ± 1.5 K suggests a peak abundance about 1200 stellar radii away from CW Leo, and the line intensities indicate a high fractional abundance with respect to H<sub>2</sub>.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 1, 2012
	+
	+	----
	+

c2h3chs

anonymous@undisclosed.example.com (Anonymous) — Fri, 27 Jun 2025 12:50:56 +0000

2025/06/27 14:35		current
Line 3:		Line 3:
	C. Cabezas, K. Vávra, G. Molpeceres, L. Kolesniková, M. Agúndez, G. Vylitová, N. Marcelino, L. Hrubčík, R. Fuentetaja, T. Uhlíková, B. Tercero, J. Koucký, G. Esplugues, P. Kania, P. de Vicente, Š. Urban, and J. Cernicharo\\		C. Cabezas, K. Vávra, G. Molpeceres, L. Kolesniková, M. Agúndez, G. Vylitová, N. Marcelino, L. Hrubčík, R. Fuentetaja, T. Uhlíková, B. Tercero, J. Koucký, G. Esplugues, P. Kania, P. de Vicente, Š. Urban, and J. Cernicharo\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1051/0004-6361/202554670\|Discovery of propenethial (CH<sub>2</sub>CHCHS) in TMC-1 — The sulphur analogue of acrolein]]\\	+	[[https://doi.org/10.1051/0004-6361/202554670\|Discovery of propenethial (CH<sub>2</sub>CHCHS) in TMC-1 − The sulphur analogue of acrolein]]\\
	//Astron. Astrophys.// 698, Art. No. L24 (2025).\\		//Astron. Astrophys.// 698, Art. No. L24 (2025).\\
-	Propenethial, also known as thioacrolein, was identified through //a//-type transitions with //J// = 6 − 5 to 9 − 8 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. Nine of the covered transitions were not or not severely blended; the signal-to-noise ratio was rather low for two of them. A value of //T//<sub>rot</sub> = 9 K was assumed. Its column density is about a factor of 36 lower than that of acetaldehyde.\\	+	Propenethial, also known as thioacrolein, was identified through //a//-type transitions with //J// = 6 − 5 to 9 − 8 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. Nine of the covered transitions were not or not severely blended; the signal-to-noise ratio was rather low for two of them. A value of //T//<sub>rot</sub> = 9 K was assumed. Its column density is about a factor of 27 and 7 lower than those of cyanothioformaldehyde andthioacetaldehyde, respectively. And it is only about a factor of 5 lower than that of propenal.\\
	\\		\\

c2h4

anonymous@undisclosed.example.com (Anonymous) — Wed, 29 Oct 2025 10:45:42 +0000

2025/10/29 11:19		current
Line 5:		Line 5:
	[[https://doi.org/10.1086/183490\|Ethylene in IRC +10216]]\\		[[https://doi.org/10.1086/183490\|Ethylene in IRC +10216]]\\
	//Astrophys. J.// 244, L103–L105 (1981).\\		//Astrophys. J.// 244, L103–L105 (1981).\\
-	6 features belonging to several more //J// = 3 –2 and 4 –3 were observed near 75.9 and near 101 GHz. The derived rotational temperature in that source was about 9 K.\\	+	Ethene, aka ethylene, was identified through two transitions (1<sub>10</sub> – 0<sub>00</sub> and 5<sub>15</sub> – 5<sub>05</sub>) of the //v//<sub>7</sub> out-of-plane infrared band near 949 cm<sup>−1</sup> observed in absorption with the 1.5 m McMath Solar Telescope of the Kitt Peak National Observatory toward the C-rich AGB star CW Leonis. A rotational temperature greater than 400 K was inferred.\\
	\\		\\

-	Much higher rotational temperatures (about 70 K) were derived in a 3, 2, and 1 mm line survey carried out with SEST:\\	+	J. P. Fonfría, K. H. Hinkle, J. Cernicharo, M. J. Richter, M. Agúndez, and L. Wallace\\
-	E. Gibb, A. Nummelin, W. M. Irvine, D. C. B. Whittet, and P. Bergman,\\	+	investigated\\
-	[[https://doi.org/10.1086/317805\|Chemistry of the Organic-Rich Hot Core G327.3–0.6]]\\	+	[[https://doi.org/10.3847/1538-4357/835/2/196\|The Abundance of C2H4 in the Circumstellar Envelope of IRC+10216]]\\
-	//Astrophys. J.// 545, 309–326 (2000).\\	+
-	\\	+
-		+
-	L. Majumdar, P. Gratier, T. Vidal, V. Wakelam, J.-C. Loison, K. M. Hickson, and E. Caux,\\	+
-	reported on the\\	+
-	[[https://doi.org/10.1093/mnras/stw457\|Detection of CH<sub>3</sub>SH in protostar IRAS 16293-2422]]\\	+
-	//Mon. Not. R. Astron. Soc.// 458, 1859–1865 (2016).\\	+
-	The IRAM 30 m telescope was used to study this solar-type pair of proto-stars at 3 mm. Here, an excitation temperature of 32 ± 4 K was derived.\\	+
-	\\	+
-		+
-	L. F. Rodríguez-Almeida, I. Jiménez-Serra, V. M. Rivilla, J. Martín-Pintado, S. Zeng, B. Tercero, P. de Vicente, Laura Colzi, F. Rico-Villas, S. Martín, and M. A. Requena-Torres\\	+
-	reported on\\	+
-	[[https://doi.org/10.3847/2041-8213/abf7cb\|Thiols in the Interstellar Medium: First Detection of HC(O)SH and Confirmation of**	+
-	C<sub>2</sub>H<sub>5</sub>SH]]\\**	+
-	//Astrophys. J. Lett.// 912 (2021), Art. No. L11.\\	+
-	This is the first unumbiguous detection of ethanethiol in the ISM. Ten lines with 2 ≤ //J// ≤ 6 and //K<sub>a</sub>// ≤ 1 were reported and shown, of which nine were unblended or marginally blended and one line was more blended. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. All lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> = 14.9 ± 0.5 K. The signal-to-noise ratios of the lines were quite good to very good. The column density of methanol is a factor of ∼24 higher.\\	+
-	\\	+
-		+
-	H. S. P. Müller, A. Belloche, L.-H. Xu, R. M. Lees, R. T. Garrod, A. Walters, J. van Wijngaarden, F. Lewen, S. Schlemmer, and K. M. Menten,\\	+
-	reported on\\	+
-	[[https://doi.org/10.1051/0004-6361/201527470\|Exploring molecular complexity with ALMA (EMoCA): Alkanethiols and alkanols in Sagittarius B2(N2)]]\\	+
-	//Astron. Astrophys.// 587, Art. No. A92 (2016).\\	+
-	A line survey of Sgr B2(N) was carried out with ALMA at 3 mm. CH<sub>3</sub>SH was not only detected in its ground vibrational state, but also in its first torsionally excited state, even though the CH<sub>3</sub>OH/CH<sub>3</sub>SH ratio was only about 120. These authors derived a rotational temperature of 180 K in this source.\\	+
-	\\	+
-		+
-	H. A. Bunn, S. Spezzano, L. H. Coudert, J.-C. Guillemin, Y. Lin, C. P. Endres, B. Billinghurst, O. Pirali, J. Jørgensen, V. Lattanzi, and P. Caselli\\	+
-	reported on\\	+
-	[[https://doi.org/10.3847/2041-8213/adacea\|Laboratory Rotational Spectroscopy Leads to the First Interstellar Detection of Singly Deuterated Methyl Mercaptan (CH2DSH)]]\\	+
	//Astrophys. J. Lett.// 980, Art. No. L13 (2025).\\		//Astrophys. J. Lett.// 980, Art. No. L13 (2025).\\
-	The isotopolog was identified in the Protostellar Interferometric Line Survey (PILS) toward the solar-like protostar IRAS 16293−2422 B. Eight lines were detected that were deemed to be unblended or only slightly blended. Several other transitions were covered, but most of them were severely blended. The derived CH<sub>2</sub>DSH to CH<sub>3</sub>SH ratio is about 0.055. An earlier search for CH<sub>3</sub>SD by [[https://doi.org/10.1051/0004-6361/201834472\|O. Zhakharenko et al.]], //Astron. Astrophys.// 621, Art. No. A114 (2019) was unsuccessful and, with respect to the present finding, not particularly constraining.\\	+	The Texas Echelon Cross Echelle Spectrograph (TEXES) at the NASA Infrared Telescope Facility (IRTF) was employed to observe 80 transitions of the //v//<sub>7</sub> band with //J// up to about 30 toward CW Leonis. About 1/3 of the lines are unblended with rotational temperatures of about 105 and 400 K and the fractional abundance with respect to H<sub>2</sub> around 10<sup>−8</sup>.\\
	\\		\\

c2n

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:41:13 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Circumstellar Cyanomethylidyne, C2N =====
	+
	+	J. K. Anderson and L. M. Ziurys,\\
	+	reported on the\\
	+	[[https://doi.org/10.1088/2041-8205/795/1/L1\|Detection of CCN (//X// <sup>2</sup>Π<sub>r</sub>) in IRC+10216: Constraining Carbon-chain Chemistry]],\\
	+	//Astrophys. J.// 795 Art. No. L1 (2014).\\
	+	The ARO 12 m and the ARO SMT were used to detect the two Λ-doubling components each of three rotational transitions in the <sup>2</sup>Π<sub>1/2</sub> lower energy spin ladder: the //J// = 9.5 – 8.5, 6.5 – 5.5, and the 4.5 – 3.5 transitions near 224.45, 153.63, and 106.36 GHz in the circumstellar envelope of CW Leonis. According to the authors, the higher frequency //f//-components are always unblended, whereas the //e//-components are always partially blended. Because of its rather low abundance, ratios of about 500 : 1 : 50 were derived for CN, C<sub>2</sub>N, and C<sub>3</sub>N, and its small dipole moment, the molecule was very hard to detect.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2014
	+
	+	----
	+

c3_aldehydes

anonymous@undisclosed.example.com (Anonymous) — Wed, 14 Jul 2021 08:59:30 +0000

2021/02/23 12:57		current
Line 40:		Line 40:
	[[https://doi.org/10.1051/0004-6361/202038113\|The ALMA-PILS Survey: First Detection of the Unsaturated Three-carbon Molecules Propenal (C<sub>2</sub>H<sub>3</sub>CHO) and Propylene (C<sub>3</sub>H<sub>6</sub>) towards the Low-mass Protostar IRAS 16293–2422 B]]\\		[[https://doi.org/10.1051/0004-6361/202038113\|The ALMA-PILS Survey: First Detection of the Unsaturated Three-carbon Molecules Propenal (C<sub>2</sub>H<sub>3</sub>CHO) and Propylene (C<sub>3</sub>H<sub>6</sub>) towards the Low-mass Protostar IRAS 16293–2422 B]]\\
	//Astrophys. J.// 645, Art. No. A53 (2021).\\		//Astrophys. J.// 645, Art. No. A53 (2021).\\
-	This report is actually the first one on an umambiguous (i.e. multi line) detection of propenal in the ISM. It is also the first one on the detection of warm (~125 K) propenal in the ISM as well as on the detection of propanal around a low-mass protostar. The Protostellar Interferometric Line Survey (PILS) was carried out with ALMA in its Band 7 (329 – 363 GHz) with additional observations in Band 6. A total of 15 different unblended (with respect to a different molecule) lines were identified.	+	This report is actually the first one on an umambiguous (i.e. multi line) detection of propenal in the ISM. It is also the first one on the detection of warm (~125 K) propenal in the ISM and on the detection of propanal around a low-mass protostar. The Protostellar Interferometric Line Survey (PILS) was carried out with ALMA in its Band 7 (329 – 363 GHz) with additional observations in Band 6. A total of 15 different unblended (with respect to a different molecule) lines were identified.\\

	----		----

-	Contributor(s): H. S. P. Müller; 07, 2004; 07, 2012; 02, 2016; 01, 2017; 02, 2021	+	Contributor(s): H. S. P. Müller; 07, 2004; 07, 2012; 02, 2016; 01, 2017; 02, 2021.

	----		----

c3

anonymous@undisclosed.example.com (Anonymous) — Sat, 15 Feb 2020 13:20:27 +0000

2019/10/21 17:17		current
Line 23:		Line 23:
	studied sightlines toward 20 Aql, ζ Oph, and ζ Per. Two components were detected, a warm one around 60 K and a hot one around 250 K.		studied sightlines toward 20 Aql, ζ Oph, and ζ Per. Two components were detected, a warm one around 60 K and a hot one around 250 K.

		+	T. F. Giesen, B. Mookerjea, G. W. Fuchs, A. A. Breier, D. Witsch, R. Simon, and J. Stutzki\\
		+	reported on the\\
		+	[[https://doi.org/10.1051/0004-6361/201936538\|First Detection of the Carbon Chain Molecules <sup>13</sup>CCC and C<sup>13</sup>CC towards SgrB2(M)]],\\
		+	//Astron. Astrophys.// 633 Art. No. A120 (2020).\\
		+	The average <sup>12</sup>C/<sup>13</sup>C ratio per C atom is about 20.5, in the expected range. However, C<sup>13</sup>CC is slightly overabundant with a ratio of 14.8 ± 2.7 whereas <sup>13</sup>CCC is underabundant with a ratio of 12.7 ± 2.8; the latter value corresponds to a <sup>12</sup>C/<sup>13</sup>C ratio per C atom of 25.4 ± 5.6 because of two equivalent terminal C atoms.\\

	----		----

-	Contributor(s): H. S. P. Müller; 08, 2010	+	Contributor(s): H. S. P. Müller; 08, 2010; 02, 2020

	----		----

c3h-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 08 Mar 2022 15:31:17 +0000

c3h3

anonymous@undisclosed.example.com (Anonymous) — Thu, 20 May 2021 09:33:44 +0000

2021/05/11 16:57		current
Line 1:		Line 1:
	===== On Propargyl in the ISM =====		===== On Propargyl in the ISM =====

-	J. Cernicharo, M. Agúndez, C. Cabezas, N. Marcelino, B. Tercero, J. R. Pardo, J. D. Gallego, F. Tercero, J. A. López-Pérez, and P. de Vicente\\	+	M. Agúndez, C. Cabezas, B. Tercero, N. Marcelino, J. D. Gallego, P. de Vicente, and J. Cernicharo\\
	reported on\\		reported on\\
	[[https://doi.org/10.1051/0004-6361/202140553\|Discovery of the propargyl radical (CH<sub>2</sub>CCH) in TMC-1: One of the most abundant radicals ever found and a key species for cyclization to benzene in cold dark clouds]]\\		[[https://doi.org/10.1051/0004-6361/202140553\|Discovery of the propargyl radical (CH<sub>2</sub>CCH) in TMC-1: One of the most abundant radicals ever found and a key species for cyclization to benzene in cold dark clouds]]\\
	//Astron. Astrophys.// 647, Art. No. L10 (2021).\\		//Astron. Astrophys.// 647, Art. No. L10 (2021).\\
-	The ethenthione, H<sub>2</sub>C<sub>2</sub>S, and propadienthione, H<sub>2</sub>C<sub>3</sub>S, molecules were identified through 6 and 7 //a//-type transitions, respectively, with //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. The column density of H<sub>2</sub>C<sub>2</sub>S is about a factor of 100 lower than that of H<sub>2</sub>CS and about a factor of two higher than that of H<sub>2</sub>C<sub>3</sub>S.\\	+	The propargyl radical was identified through the six strongest hyperfine components of the 2<sub>02</sub> − 1<sub>01</sub> rotational transition around 37460 MHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. The column density of CH<sub>2</sub>CCH is only slightly smaller than that of CH<sub>3</sub>CCH, a closed shell species.\\


Line 12:		Line 12:

	Contributor(s): H. S. P. Müller; 05, 2021		Contributor(s): H. S. P. Müller; 05, 2021
-

	----		----

c3h5cn

anonymous@undisclosed.example.com (Anonymous) — Mon, 29 Apr 2024 10:18:29 +0000

2024/01/31 12:39		current
Line 3:		Line 3:
	J. Cernicharo, R. Fuentetaja, C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, J. R. Pardo, and P. de Vicente\\		J. Cernicharo, R. Fuentetaja, C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, J. R. Pardo, and P. de Vicente\\
	reported on the\\		reported on the\\
-	**[[https://doi.org/10.1051/0004-6361/202244255\|Discovery of five cyano derivatives of propene with the QUIJOTE	+	[[https://doi.org/10.1051/0004-6361/202244255\|Discovery of five cyano derivatives of propene with the QUIJOTE line survey]]\\
-	line survey]]**\\	+
	//Astron. Astrophys.// 663, Art. No. L5 (2022).\\		//Astron. Astrophys.// 663, Art. No. L5 (2022).\\
-	The molecular line survey is of the prototypical cold dark molecular cloud TMC-1 and was carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. 2-Butenenitrile, aka 1-cyanopropene or crotononitrile, was detected in its //E// (or //trans//) and //Z// (or //cis//) stereoisomeric forms. In addition, 2-propenenitrile, aka 2-cyanopropene or methacrylonitrile was also identified as was 3-butenenitrile, aka 3-cyanopropene or allyl cyanide, in its //syn// (or //cis//) and //gauche// conformers.	+	The molecular line survey is of the prototypical cold dark molecular cloud TMC-1 and was carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. 2-Butenenitrile, aka 1-cyanopropene or crotononitrile, was detected in its //E// (or //trans//) and //Z// (or //cis//) stereoisomeric forms. In addition, 2-propenenitrile, aka 2-cyanopropene or methacrylonitrile was also identified as was 3-butenenitrile, aka 3-cyanopropene or allyl cyanide, in its //syn// (or //cis//) and //gauche// conformers. Please note that while the two 2-butenenitriles are counted as two molecules because conversion requires breaking of a double bond, the 3-butenenitriles are counted as one, even if the rotation around a single bond is at least somewhat hindered at the low temperatures of TMC-1.
	Several //a//-type transitions having 4 ≤ //J// ≤ 8 to 6 ≤ //J// ≤ 11 and //K<sub>a</sub>// ≤ 2 were identified. A value of //T//<sub>rot</sub> = 7 ± 1 K was derived through rotation diagrams in all instances. The column densities (in units of 10<sup>10</sup> cm<sup>−2</sup>) of the butenenitriles is about 5, 13, 10, 7, and 8 for the //E//-1-, //Z//-1-, 2-, //syn//-3-, and //gauche//-3-forms, respectively, compared to ~4 × 10<sup>13</sup> cm<sup>−2</sup> for propene. The combined cyanopropenes are much less abundant in relation to its parent hydrocarbon compared to other detected cyanide derivatives. It is also noteworthy to point out that, unsurprisingly, the abundances among the cyanopropenes do not at all reflect relative energies among these species.\\		Several //a//-type transitions having 4 ≤ //J// ≤ 8 to 6 ≤ //J// ≤ 11 and //K<sub>a</sub>// ≤ 2 were identified. A value of //T//<sub>rot</sub> = 7 ± 1 K was derived through rotation diagrams in all instances. The column densities (in units of 10<sup>10</sup> cm<sup>−2</sup>) of the butenenitriles is about 5, 13, 10, 7, and 8 for the //E//-1-, //Z//-1-, 2-, //syn//-3-, and //gauche//-3-forms, respectively, compared to ~4 × 10<sup>13</sup> cm<sup>−2</sup> for propene. The combined cyanopropenes are much less abundant in relation to its parent hydrocarbon compared to other detected cyanide derivatives. It is also noteworthy to point out that, unsurprisingly, the abundances among the cyanopropenes do not at all reflect relative energies among these species.\\
	\\		\\
Line 12:		Line 11:
	----		----

-	Contributor(s): H. S. P. Müller; 07, 2022	+	Contributor(s): H. S. P. Müller; 07, 2022; 01, 2024

	----		----

c3h6

anonymous@undisclosed.example.com (Anonymous) — Sun, 09 Jun 2024 11:29:15 +0000

2019/04/25 13:41		current
Line 5:		Line 5:
	[[https://doi.org/10.1086/521398\|Discovery of Interstellar Propylene (CH<sub>2</sub>CHCH<sub>3</sub>): Missing Links in Interstellar Gas-Phase Chemistry]]\\		[[https://doi.org/10.1086/521398\|Discovery of Interstellar Propylene (CH<sub>2</sub>CHCH<sub>3</sub>): Missing Links in Interstellar Gas-Phase Chemistry]]\\
	//Astrophys. J.// 665, L127–L130 (2007).\\		//Astrophys. J.// 665, L127–L130 (2007).\\
-	Six rotational transitions each split into two //A// and //E// components due to the CH<sub>3</sub> interal rotation were observed plus one //A// component for which the //E// line is overlapped. The observation of this molecule in TMC-1 was rather surprising because apparently noone in the community considered such an almost saturated molecule to be likely in this source – especially because of thus far missing routes to this molecule. Even more remarkable is the detection because of the high abundance; a column density of 4 × 10<sup>13</sup> cm<sup>-2</sup> was derived; comparable to the abundance of //c//-C<sub>3</sub>H<sub>2</sub>.	+	Six rotational transitions each split into two //A// and //E// components due to the CH<sub>3</sub> interal rotation were observed plus one //A// component for which the //E// line is overlapped. The observation of this molecule in TMC-1 was rather surprising because apparently noone in the community considered such an almost saturated molecule to be likely in this source – especially because of thus far missing routes to this molecule. Even more remarkable is the detection because of the high abundance; a column density of 4 × 10<sup>13</sup> cm<sup>-2</sup> was derived; comparable to the abundance of //c//-C<sub>3</sub>H<sub>2</sub>.\\
		+	\\

	M. Agúndez, J. Cernicharo, and M. Guélin\\		M. Agúndez, J. Cernicharo, and M. Guélin\\
Line 11:		Line 12:
	[[https://doi.org/10.1051/0004-6361/201526317\|Discovery of Interstellar Ketenyl (HCCO), a Surprisingly Abundant Radical]]\\		[[https://doi.org/10.1051/0004-6361/201526317\|Discovery of Interstellar Ketenyl (HCCO), a Surprisingly Abundant Radical]]\\
	//Astron. Astrophys.// 577, Art. No. L5 (2015).\\		//Astron. Astrophys.// 577, Art. No. L5 (2015).\\
-	Emission of up to three more rotational transitions were also detected.	+	Emission of up to three more rotational transitions were also detected.\\
		+	\\
		+
		+	S. Manigand, A. Coutens, J.-C. Loison, V. Wakelam, H. Calcutt, H. S. P. Müller, J. K. Jørgensen, V. Taquet, S. F. Wampfler, T. L. Bourke, B. M. Kulterer, E. F. van Dishoeck, M. N. Drozdovskaya, and N. F. W. Ligterink\\
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/202038113\|The ALMA-PILS Survey: First Detection of the Unsaturated Three-carbon Molecules Propenal (C<sub>2</sub>H<sub>3</sub>CHO) and Propylene (C<sub>3</sub>H<sub>6</sub>) towards the Low-mass Protostar IRAS 16293–2422 B]]\\
		+	//Astron. Astrophys.// 645, Art. No. A53 (2021).\\
		+	This is the first account on luke-warm (~ 75 K) propene in the ISM and on the detection of propene around a low-mass protostar. The Protostellar Interferometric Line Survey (PILS) was carried out with ALMA in its Band 7 (329 – 363 GHz) with additional observations in Band 6. A total of 17 different unblended (with respect to a different molecule) lines were identified.


	----		----

-	Contributor(s): H. S. P. Müller; 08, 2007; 05, 2015	+	Contributor(s): H. S. P. Müller; 08, 2007; 05, 2015; 02, 2021

c3h6o3

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:15:19 +0000

c3n-minus

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Sep 2020 15:05:02 +0000

2019/10/22 17:08		current
Line 6:		Line 6:
	//Astrophys. J.// 677, 1132–1139 (2008).\\		//Astrophys. J.// 677, 1132–1139 (2008).\\
	This anion is isolelectronic to C<sub>4</sub>H<sup>–</sup>. Besides the presently more common C<sub>2n</sub>H<sup>–</sup> family, it is the first member of a second family of anions detected in space, C<sub>2n–1</sub>N<sup>–</sup>.\\		This anion is isolelectronic to C<sub>4</sub>H<sup>–</sup>. Besides the presently more common C<sub>2n</sub>H<sup>–</sup> family, it is the first member of a second family of anions detected in space, C<sub>2n–1</sub>N<sup>–</sup>.\\
-	It was searched for, but not found in TMC-1.	+	It was searched for, but not found in TMC-1.\\
		+
		+	Meanwhile,\\
		+	J. Cernicharo, N. Marcelino, J. R. Pardo, M. Agúndez, B. Tercero, P. de Vicente, C. Cabezas, and C. Bermúdez\\
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/202039231\|Interstellar nitrile anions: Detection of C<sub>3</sub>N<sup>–</sup> and C<sub>5</sub>N<sup>–</sup> in TMC-1]]\\
		+	//Astron. Astrophys.// 641, Art. No. L9 (2020).\\


	----		----

-	Contributor(s): H. S. P. Müller; 4, 2008	+	Contributor(s): H. S. P. Müller; 04, 2008; 09, 2020

	----		----

c4h-minus

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:16:41 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of the Butadiynylide Ion, C4H–, in Space =====
	+
	+	The butadiynylide ion has been detected toward the carbon rich star IRC +10216 in 5 rotational transitions from //J// = 9 – 8 to 15 – 14 which occur in the 3 and 2 mm regions:\\
	+	J. Cernicharo, M. Guélin, M. Agúndez, K. Kawaguchi, M. C. McCarthy, and P. Thaddeus,\\
	+	[[https://doi.org/10.1051/0004-6361:20077415\|Astronomical Detection of C<sub>4</sub>H<sup>–</sup>, the Second Interstellar Anion]]\\
	+	//Astron. Astrophys.// 467, L37–L40 (2007).\\
	+	Several additional transitions of C<sub>6</sub>H<sup>–</sup>, detected and reported earlier, were also observed.
	+
	+	The molecule was detected tentatively toward a low-mass protostar:\\
	+	N. Sakai, T. Sakai, and S. Yamamoto,\\
	+	[[https://doi.org/10.1086/527376\|Tentative Detection of C<sub>4</sub>H<sup>–</sup> toward the Low-Mass Protostar IRAS 04368+2557 in L1527]]\\
	+	//Astrophys. J.// 673, L71–L74 (2008);\\
	+	this detection was confirmed in a rather extensive study of anions and related neutral species:\\
	+	M. Agúndez, J. Cernicharo, M. Guélin, M. Gerin, M. C. McCarthy, and P. Thaddeus,\\
	+	[[https://doi.org/10.1051/0004-6361:20078985\|Search for Anions in Molecular Sources: C<sub>4</sub>H<sup>–</sup> Detection in L1527]]\\
	+	//Astron. Astrophys.// 478, L19–L22 (2008).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 5, 2007; 1, 2008
	+
	+	----
	+

c4h

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 14:57:02 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Butadiynyl, C4H, in Space =====
	+
	+	The butadiynyl radical in its <sup>2</sup>Σ ground vibrational state has been detected between 85 and 115 GHz with the NRAO 11 m telescope in the circumstellar envelope of the carbon-rich late-type star CW Leo, also known as IRC +10216, in eight fine structure lines of four rotational transitions (//N// = 9 – 8 to 12 – 11) by\\
	+	M. Guélin, S. Green, and P. Thaddeus,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1978ApJ...224L..27G\|Detection of the C<sub>4</sub>H Radical toward IRC +10216]],\\
	+	//Astrophys. J.// 224 L27–L30 (1978)\\
	+	before it was actually detected in the laboratory. Two rotational transitions had been reported previously as U-lines in two different publications. The highest frequency fine structure component seems to be overlapped.
	+
	+	Soon thereafter, it was detected with the OSO 20 m telescope toward TMC-1 by:\\
	+	W. M. Irvine, B. Höglund, P. Friberg, J. Askne, and J. Elldér,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1981ApJ...248L.113I\|The Increasing Chemical Complexity of the Taurus Dark Clouds – Detection of CH<sub>3</sub>CCH and C<sub>4</sub>H]],\\
	+	//Astrophys. J.// 248 L113–L117 (1981).\\
	+	Four hyperfine components of the //N// = 3 – 2 transition were detected near 28.55 GHz.
	+
	+	The radical was also observed in the diffuse medium by:\\
	+	M. B. Bell, P. A. Friedman, and H. E. Matthews,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1983ApJ...273L..35B\|The Detection of Butadiynyl (C<sub>4</sub>H) in Absorption against Cassiopeia A]],\\
	+	//Astrophys. J.// 273 L35–L39 (1983).
	+
	+	Moreover, the molecule was also detected in several PDRs, namely the Horsehead nebula (B 33), IC 63, and in the //ρ// Oph L1688-W cloud interface:\\
	+	D. Teyssier, D. Fossé M. Gerin, J. Pety, A. Abergel, and E. Roueff,\\
	+	[[https://doi.org/10.1051/0004-6361:20034534\|Carbon Budget and Carbon Chemistry in Photon Dominated Regions]],\\
	+	//Astron. Astrophys.// 417 135–149 (2004).
	+
	+	Vibrationally excited C<sub>4</sub>H was also detected:\\
	+	M. Guélin, J. Cernicharo, S. Navarro, D. R. Woodward, C. A. Gottlieb, and P. Thaddeus,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...182L..37G\|New doublets in IRC +10216 – Vibrationally Excited C<sub>4</sub>H?]],\\
	+	//Astron. Astrophys.// 182 L37–L39 (1987).\\
	+	Subsequent laboratory work revealed these transitions to be due to the //v//<sub>7</sub> = 1 Π state and the //v//<sub>7</sub> = 2 Σ and Δ states:\\
	+	S. Yamamoto, S. Saito, M. Guélin, J. Cernicharo, H. Suzuki, and M. Ohishi,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987ApJ...323L.149Y\|Laboratory Microwave Spectroscopy of the Vibrational Satellites for the //ν//<sub>7</sub> and 2//ν//<sub>7</sub> states of C<sub>4</sub>H and their Astronomical Identification]],\\
	+	//Astrophys. J.// 323 L149–L153 (1987).\\
	+	Unfortunately, no laboratory data is available for higher excited vibrational states !
	+
	+	C<sub>4</sub>D was detected toward TMC-1 by:\\
	+	B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989ApJ...347L..39T\|Detection of C<sub>4</sub>D – Implications for Ion-Molecule Chemistry]],\\
	+	//Astrophys. J.// 347 L39–L42 (1989).
	+
	+	The detection of the <sup>13</sup>C isotopic species was reported in:\\
	+	J. Cernicharo, M. Guélin, and C. Kahane,\\
	+	[[https://ui.adsabs.harvard.edu/abs/2000A%26AS..142..181C\|A λ 2 mm Molecular Line Survey of the C-star Envelope IRC+10216]],\\
	+	//Astron. Astrophys. Suppl. Ser.// 142 181–215 (2000).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 5, 2007
	+
	+	----
	+

c4h4

anonymous@undisclosed.example.com (Anonymous) — Thu, 20 May 2021 09:34:25 +0000

2021/05/12 12:17		current
Line 1:		Line 1:
	===== On Butenyne in the ISM =====		===== On Butenyne in the ISM =====

-	M. Agúndez, C. Cabezas, B. Tercero, N. Marcelino, J. D. Gallego, P. de Vicente, and J. Cernicharo\\	+	J. Cernicharo, M. Agúndez, C. Cabezas, N. Marcelino, B. Tercero, J. R. Pardo, J. D. Gallego, F. Tercero, J. A. López-Pérez, and P. de Vicente\\
	reported on\\		reported on\\
	[[https://doi.org/10.1051/0004-6361/202140434\|Discovery of CH<sub>2</sub>CHCCH and detection of HCCN, HC<sub>4</sub>N, CH<sub>3</sub>CH<sub>2</sub>CN, and, tentatively, CH<sub>3</sub>CH<sub>2</sub>CCH in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202140434\|Discovery of CH<sub>2</sub>CHCCH and detection of HCCN, HC<sub>4</sub>N, CH<sub>3</sub>CH<sub>2</sub>CN, and, tentatively, CH<sub>3</sub>CH<sub>2</sub>CCH in TMC-1]]\\
	//Astron. Astrophys.// 647, Art. No. L2 (2021).\\		//Astron. Astrophys.// 647, Art. No. L2 (2021).\\
-	Butenyne, aka vinylacetylene, was identified through 6 //a//-type transitions with 3 ≤ //J// ≤ 5 and //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of //T//<sub>rot</sub> = 5.0 ± 0.5 K was derived. The column density of butenyne is about a factor of 1.8 than that of the isoelectronic vinyl cyanide.\\	+	Butenyne, aka vinylacetylene, was identified through 6 //a//-type transitions with 3 ≤ //J// ≤ 5 and //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of //T//<sub>rot</sub> = 5.0 ± 0.5 K was derived. The column density of butenyne is about a factor of 1.8 higher than that of the isoelectronic vinyl cyanide.\\

c4si

anonymous@undisclosed.example.com (Anonymous) — Fri, 08 Aug 2025 13:47:35 +0000

2019/10/23 16:57		current
Line 1:		Line 1:
-	===== On the Detection of Butadiynylidenesilylidyne =====	+	===== On the Detection of Tetratrienediylidenesilylene =====

-	Six transitions of butadiynylidenesilylidyne with //J"// between 11 and 27 were detected in the circumstellar envelope of CW Leo (IRC +10216) with the 45 m radiotelescope of the Nobeyama Radio Observatory between 36 and 86 GHz:\\	+	Six transitions of tetratrienediylidenesilylene, also known as silapentatetraenediylidene, with //J"// between 11 and 27 were detected in the circumstellar envelope of CW Leonis (IRC +10216) with the 45 m radiotelescope of the Nobeyama Radio Observatory between 36 and 86 GHz:\\
	M. Ohishi, N. Kaifu, K. Kawaguchi, A. Murakami, S. Saito, S. Yamamoto, S.-I. Ishikawa, Y. Fujita, Y. Shiratori, and W. M. Irvine,\\		M. Ohishi, N. Kaifu, K. Kawaguchi, A. Murakami, S. Saito, S. Yamamoto, S.-I. Ishikawa, Y. Fujita, Y. Shiratori, and W. M. Irvine,\\
	[[https://ui.adsabs.harvard.edu/abs/1989ApJ...345L..83O\|Detection of a new Circumstellar Carbon Chain Molecule, C<sub>4</sub>Si]]\\		[[https://ui.adsabs.harvard.edu/abs/1989ApJ...345L..83O\|Detection of a new Circumstellar Carbon Chain Molecule, C<sub>4</sub>Si]]\\
	//Astrophys. J.// 345, L83–L86 (1989).\\		//Astrophys. J.// 345, L83–L86 (1989).\\
		+	\\

		+	In their work\\
		+	[[https://doi.org/10.1051/0004-6361/202555902\|Detection of SiC<sub>6</sub> in IRC +10216 through //Q//-band lines]]\\
		+	//Astron. Astrophys.// 700, L6 (2025).\\
		+	J. R. Pardo, J. P. Fonfría, M. Agúndez, B. Tercero, C. Cabezas, L. Velilla-Prieto, M. Guélin, P. de Vicente, and J. Cernicharo\\
		+	reported also the secure and marginal detections of <sup>29</sup>SiC<sub>4</sub> and <sup>30</sup>SiC<sub>4</sub>, respectively, by applying the <sup>28</sup>Si/<sup>29</sup>Si and <sup>30</sup>Si/<sup>29</sup>Si raios of 15.4 and 20.3, respectively, expected for the circumstellar envelope of CW Leonis. The observations are part of a 31.0 to 50.1 GHz line survey of this source with the 40 m Yebes telescope.\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller; 08, 2010	+	Contributor(s): H. S. P. Müller; 08, 2010; 08, 2025

	----		----

c5

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 14:54:45 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Pentatetraenediylidene, C5, in Space =====
	+
	+	The pure carbon chain molecule pentatetraenediylidene, C<sub>5</sub>, has been detected in the circumstellar envelope of the famous carbon star CW Leo, aka IRC +10216, by\\
	+	P. F. Bernath, K. H. Hinkle, and J. J. Keady,\\
	+	[[https://doi.org/10.1126/science.244.4904.562\|Detection of C<sub>5</sub> in the Circumstellar Shell of IRC +10216]],\\
	+	//Science// 244, 562–564 (1989)\\
	+	before it was actually detected in the laboratory. 16 //P// and //R// branch transitions of the ν<sub>3</sub> band were detected around 2169 cm<sup>–1</sup> of which 13 appear to be unblended.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 08, 2010
	+
	+	----
	+

c5h-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 08 Mar 2022 15:25:44 +0000

2022/03/08 16:21		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202142992\|Discovery of C<sub>5</sub>H<sup>+</sup> and Detection of C<sub>3</sub>H<sup>+</sup> in TMC-1 with the QUIJOTE Line Survey]],\\		[[https://doi.org/10.1051/0004-6361/202142992\|Discovery of C<sub>5</sub>H<sup>+</sup> and Detection of C<sub>3</sub>H<sup>+</sup> in TMC-1 with the QUIJOTE Line Survey]],\\
	//Astron. Astrophys.// 657, Art. No. L16 (2022).\\		//Astron. Astrophys.// 657, Art. No. L16 (2022).\\
-	Pentadiynylidynium, C<sub>5</sub>H<sup>+</sup>, was identified through four successive transitions, //J// = 7 − 6 near 33.8 GHz to //J// = 10 − 9 near 48.2 GHz in the course of a line survey carried out with the 40 m Yebes radio telescope.	+	Pentadiynylidynium, C<sub>5</sub>H<sup>+</sup>, was identified through four successive transitions, //J// = 7 − 6 near 33.8 GHz to //J// = 10 − 9 near 48.2 GHz, in the course of a line survey carried out with the 40 m Yebes radio telescope. The molecule is a factor of 3.7 ± 0.5 more abundant than C<sub>3</sub>H<sup>+</sup>, which was explained by the reactivity of the latter with H<sub>2</sub> through chemical modeling.\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 03, 2022
		+
		+	----

c5h

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 19:58:01 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Pentadiynylidyne, C5H, in Space =====
	+
	+	The pentadiynylidyne radical in its <sup>2</sup>Π<sub>1/2</sub> lower spin component has been detected in six lines of three rotational transitions toward IRC +10216 by\\
	+	J. Cernicharo, C. Kahane, J. Gómez-González; and M. Guélin,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1986A%26A...164L...1C\|Tentative Detection of the C<sub>5</sub>H Radical]],\\
	+	//Astron. Astrophys.// 164, L1–L4 (1986)\\
	+	before it was actually detected in the laboratory.
	+
	+	Confirmation came also through the observation of four lines pertaining to the <sup>2</sup>Π<sub>3/2</sub> upper spin component in the 3 mm range for which the //λ//-doubling is just not resolvable:\\
	+	J. Cernicharo, C. Kahane, J. Gómez-González; and M. Guélin,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1986A%26A...167L...5C\|Detection of the <sup>2</sup>Π<sub>3/2</sub> State of C<sub>5</sub>H]],\\
	+	//Astron. Astrophys.// 167, L5–L7 (1986).
	+
	+	Subsequently, it was also detected toward TMC-1 in one transition with resolved <sup>1</sup>H hyperfine splitting as well as //λ//-doubling:\\
	+	J. Cernicharo, M. Guélin, and C. M. Walmsley,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...172L...5C\|Detection of the Hyperfine Structure of the C<sub>5</sub>H Radical]],\\
	+	//Astron. Astrophys.// 172, L5–L6 (1987).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2007
	+
	+	----
	+

c5h3n-isomere

anonymous@undisclosed.example.com (Anonymous) — Thu, 26 Aug 2021 11:32:23 +0000

2021/04/12 16:58		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/abdbb9\|Discovery of Interstellar //trans//-Cyanovinylacetylene (HC≡CCH=CHC≡N) and Vinylcyanoacetylene (H<sub>2</sub>C=CHC<sub>3</sub>N) in GOTHAM Observations of TMC-1]]\\		[[https://doi.org/10.3847/2041-8213/abdbb9\|Discovery of Interstellar //trans//-Cyanovinylacetylene (HC≡CCH=CHC≡N) and Vinylcyanoacetylene (H<sub>2</sub>C=CHC<sub>3</sub>N) in GOTHAM Observations of TMC-1]]\\
	//Astrophys. J. Lett.// 908, Art. No. L11 (2021).\\		//Astrophys. J. Lett.// 908, Art. No. L11 (2021).\\
-	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. 2E-Penten-4-ynenitrile (here called //trans//-E-cyanovinylacetylene) and cyanoethynylethene (aka 4-penten-2-ynenitrile, here called vinylcyanoacetylene) were indentified through line-stacking with decent signal-to-noise ratios and very similar abundances. The significance of the cyanoethynylethene detections is somewhat on the edge (5.5σ). Two other isomers, 2Z-Penten-4-ynenitrile (here called //trans//-Z-cyanovinylacetylene) and //cis//-cyanovinylacetylene, were not identified.	+	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. 2E-Penten-4-ynenitrile (here called //trans//-E-cyanovinylacetylene) and cyanoethynylethene (aka 4-penten-2-ynenitrile, here called vinylcyanoacetylene) were indentified through line-stacking with decent signal-to-noise ratios and very similar abundances. The significance of the cyanoethynylethene detections is somewhat on the edge (5.5σ). Two other isomers, 2Z-Penten-4-ynenitrile (here called //trans//-Z-cyanovinylacetylene) and 2-methylene-3-butynenitrile (here called //cis//-cyanovinylacetylene), were not identified.\\

c5h4

anonymous@undisclosed.example.com (Anonymous) — Fri, 14 Nov 2025 12:15:21 +0000

2024/08/15 14:52		current
Line 7:		Line 7:
	[[https://doi.org/10.1051/0004-6361/202140482\|Discovery of allenyl acetylene, H<sub>2</sub>CCCHCCH in TMC-1 − study of the isomers of C<sub>5</sub>H<sub>4</sub>]]\\		[[https://doi.org/10.1051/0004-6361/202140482\|Discovery of allenyl acetylene, H<sub>2</sub>CCCHCCH in TMC-1 − study of the isomers of C<sub>5</sub>H<sub>4</sub>]]\\
	//Astron. Astrophys.// 647, Art. No. L3 (2021).\\		//Astron. Astrophys.// 647, Art. No. L3 (2021).\\
-	Ethynylallene, aka allenylacetylene or 1,2-pentadien-4-yne, was identified through 16 unblended or slightly blended //a//-type transitions with 6 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 3 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. The signal-to-noise ratio of the //K<sub>a</sub>// = 3 lines of these is on the edge, but the model supports the assignments. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived through a rotation diagram, but the model is more compatible with 7 K. The column density of butenyne is about a factor of 4.5 higher than that of the isoelectronic allenyl cyanide. It is, in addition, similar to that of butenyne, a factor of 5 lower than that of the methyldiacetylene isomer (aka butadienyne), and a factor of 10 lower than that of methylacetylene (aka propyne).\\	+	Ethynylallene, aka allenylacetylene or 1,2-pentadien-4-yne, was identified through 16 unblended or slightly blended //a//-type transitions with 6 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 3 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. The signal-to-noise ratio of the //K<sub>a</sub>// = 3 lines of these is on the edge, but the model supports the assignments. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived through a rotation diagram, but the model is more compatible with 7 K. The column density of butenyne is about a factor of 4.5 higher than that of the isoelectronic allenyl cyanide. It is, in addition, similar to that of butenyne, a factor of 5 lower than that of the methyldiacetylene isomer (aka 1,3-pentadiyne), and a factor of 10 lower than that of methylacetylene (aka propyne).\\
	\\		\\

Line 16:		Line 16:
	[[https://doi.org/10.1051/0004-6361/202348777\|Discovery of allenyl acetylene, Discovery of HCCCH<sub>2</sub>CCH in TMC-1 with the QUIJOTE line survey]]\\		[[https://doi.org/10.1051/0004-6361/202348777\|Discovery of allenyl acetylene, Discovery of HCCCH<sub>2</sub>CCH in TMC-1 with the QUIJOTE line survey]]\\
	//Astron. Astrophys.// 688, Art. No. L15 (2024).\\		//Astron. Astrophys.// 688, Art. No. L15 (2024).\\
-	1,4-Pentadiyne was identified through 18 unblended or slightly blended //b//-type transitions with 2 ≤ //J// ≤ 12 and //K<sub>a</sub>// ≤ 2 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.5 and 49.6 GHz. A value of //T//<sub>rot</sub> = 9.5 ± 0.5 K was derived. The column density of 1,4-pentadiyne is about a factor of 1.4 higher than that of the isoelectronic mono cyanide and about a factor of 1.4 less abundant than the ethynylallene isomer.\\	+	1,4-Pentadiyne was identified through 18 mostly unblended or slightly blended //b//-type transitions with 2 ≤ //J// ≤ 12 and //K<sub>a</sub>// ≤ 2 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.5 and 49.6 GHz. A value of //T//<sub>rot</sub> = 9.5 ± 0.5 K was derived. The column density of 1,4-pentadiyne is about a factor of 1.4 higher than that of the isoelectronic mono cyanide and about a factor of 1.4 less abundant than the ethynylallene isomer.\\
	\\		\\

c5n-minus

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Sep 2020 15:06:09 +0000

2019/05/09 12:41		current
Line 12:		Line 12:
	An additional line, U33332.3, reported by\\		An additional line, U33332.3, reported by\\
	K. Kawaguchi, Y. Kasai, S.-I. Ishikawa, and N. Kaifu,\\		K. Kawaguchi, Y. Kasai, S.-I. Ishikawa, and N. Kaifu,\\
-	[[http://cdsads.u-strasbg.fr/abs/1995PASJ...47..853K\|A Spectral-Line Survey Observation of IRC +10216 between 28 and 50 GHz]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1995PASJ...47..853K\|A Spectral-Line Survey Observation of IRC +10216 between 28 and 50 GHz]]\\
	//Publ. Astron. Soc. Japan// 47, 853–876 (1995),\\		//Publ. Astron. Soc. Japan// 47, 853–876 (1995),\\
	is, at least in part, due to C<sub>5</sub>N<sup>–</sup>.\\		is, at least in part, due to C<sub>5</sub>N<sup>–</sup>.\\
-	This anion is isolelectronic to C<sub>6</sub>H<sup>–</sup> which was the first molecular anion to be detected in space. In addition, it is a sibling of the recently detected C<sub>3</sub>N<sup>–</sup>.	+	This anion is isolelectronic to C<sub>6</sub>H<sup>–</sup> which was the first molecular anion to be detected in space. In addition, it is a sibling of the recently detected C<sub>3</sub>N<sup>–</sup>.\\

		+	Meanwhile,\\
		+	J. Cernicharo, N. Marcelino, J. R. Pardo, M. Agúndez, B. Tercero, P. de Vicente, C. Cabezas, and C. Bermúdez\\
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/202039231\|Interstellar nitrile anions: Detection of C<sub>3</sub>N<sup>–</sup> and C<sub>5</sub>N<sup>–</sup> in TMC-1]]\\
		+	//Astron. Astrophys.// 641, Art. No. L9 (2020).\\

-	----

-	Contributor(s): H. S. P. Müller; 10, 2008	+	----

		+	Contributor(s): H. S. P. Müller; 10, 2008; 09, 2020

	----		----

c5n

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 20:04:02 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Cyanobutadiynyl in the ISM =====
	+
	+	Cyanobutadiynyl, C<sub>5</sub>N, has been detected first toward TMC-1 and tentatively toward IRC+10216:\\
	+	M. Guélin, N. Neininger, and J. Cernicharo,\\
	+	[[https://ui.adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1998A%26A...335L...1G\|Astronomical Detection of the Cyanobutadiynyl Radical C<sub>5</sub>N]]\\
	+	//Astron. Astrophys.// 335, L1–L4 (1998).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2003
	+
	+	----
	+

c6h-minus

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:34:11 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	The hexatriynylide ion is the first anion that has been detected in space by radioastronomical means in 1995.\\		The hexatriynylide ion is the first anion that has been detected in space by radioastronomical means in 1995.\\
	M. C. McCarthy, C. A. Gottlieb, H. Gupta, and P. Thaddeus,\\		M. C. McCarthy, C. A. Gottlieb, H. Gupta, and P. Thaddeus,\\
-	[[http://dx.doi.org/10.1086/510238\|Laboratory and Astronomical Identification of the Negative Molecular Ion C<sub>6</sub>H<sup>–</sup>]]\\	+	[[https://doi.org/10.1086/510238\|Laboratory and Astronomical Identification of the Negative Molecular Ion C<sub>6</sub>H<sup>–</sup>]]\\
	//Astrophys. J.// 652, L141–L144 (2006)\\		//Astrophys. J.// 652, L141–L144 (2006)\\
	reported microwave and millimeter-wave transitions of the molecule and the detection of two rotational transitions of this ion (//J// = 4 – 3 and 5 – 4) in TMC-1.\\		reported microwave and millimeter-wave transitions of the molecule and the detection of two rotational transitions of this ion (//J// = 4 – 3 and 5 – 4) in TMC-1.\\
Line 13:		Line 13:
	More recently, three transitions have been detected toward a low-mass protostar:\\		More recently, three transitions have been detected toward a low-mass protostar:\\
	N. Sakai, T. Sakai, Y. Osamura, and S. Yamamoto,\\		N. Sakai, T. Sakai, Y. Osamura, and S. Yamamoto,\\
-	[[http://dx.doi.org/10.1086/521979\|Detection of C<sub>6</sub>H<sup>–</sup> toward the Low-Mass Protostar IRAS 04368+2557 in L1527]]\\	+	[[https://doi.org/10.1086/521979\|Detection of C<sub>6</sub>H<sup>–</sup> toward the Low-Mass Protostar IRAS 04368+2557 in L1527]]\\
	//Astrophys. J.// 667, L65–L68 (2007).		//Astrophys. J.// 667, L65–L68 (2007).

Line 20:		Line 20:

	Contributor(s): H. S. P. Müller; 11, 2006; 1, 2008		Contributor(s): H. S. P. Müller; 11, 2006; 1, 2008
-

	----		----

c6h

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:30:30 +0000

c6h2

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:39:53 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	Hexapentaenylidene in its <sup>1</sup>A<sub>1</sub> ground electronic state has been detected with the 70 m DSN antenna in emission in two rotational transitions toward the dark cloud TMC-1 by\\		Hexapentaenylidene in its <sup>1</sup>A<sub>1</sub> ground electronic state has been detected with the 70 m DSN antenna in emission in two rotational transitions toward the dark cloud TMC-1 by\\
	W. D. Langer, T. Velusamy, T. B. H. Kuiper, R. Peng, M. C. McCarthy, M. J. Travers, A. Kovács, C. A. Gottlieb, and P. Thaddeus,\\		W. D. Langer, T. Velusamy, T. B. H. Kuiper, R. Peng, M. C. McCarthy, M. J. Travers, A. Kovács, C. A. Gottlieb, and P. Thaddeus,\\
-	[[http://dx.doi.org/10.1086/310622\|First Astronomical Detection of the Cumulene Carbon Chain Molecule H<sub>2</sub>C<sub>6</sub> in TMC-1]],\\	+	[[https://doi.org/10.1086/310622\|First Astronomical Detection of the Cumulene Carbon Chain Molecule H<sub>2</sub>C<sub>6</sub> in TMC-1]],\\
	//Astrophys. J.// 480, L63–L66 (1997)\\		//Astrophys. J.// 480, L63–L66 (1997)\\
	The //ortho// transitions 7<sub>1,7</sub> – 6<sub>1,6</sub> and 8<sub>1,8</sub> – 7<sub>1,7</sub> near 18.8 and 21.5 GHZ, respectively, were detected. The lighter homolog C<sub>4</sub>H<sub>2</sub> is about 25 times more abundant.		The //ortho// transitions 7<sub>1,7</sub> – 6<sub>1,6</sub> and 8<sub>1,8</sub> – 7<sub>1,7</sub> near 18.8 and 21.5 GHZ, respectively, were detected. The lighter homolog C<sub>4</sub>H<sub>2</sub> is about 25 times more abundant.
Line 10:		Line 10:
	M. Araki, S. Takano, N. Sakai, S. Yamamoto, T. Oyama, N. Kuze, and K. Tsukiyama,\\		M. Araki, S. Takano, N. Sakai, S. Yamamoto, T. Oyama, N. Kuze, and K. Tsukiyama,\\
	who studied\\		who studied\\
-	[[http://dx.doi.org/10.3847/1538-4357/aa8637\|Long Carbon Chains in the Warm Carbon-chain-chemistry Source L1527: First Detection of C<sub>7</sub>H in Molecular Clouds]],\\	+	[[https://doi.org/10.3847/1538-4357/aa8637\|Long Carbon Chains in the Warm Carbon-chain-chemistry Source L1527: First Detection of C<sub>7</sub>H in Molecular Clouds]],\\
	//Astrophys. J.// 847 Art. No. 51 (2017).\\		//Astrophys. J.// 847 Art. No. 51 (2017).\\
	The three //J// = 16 – 15 transitions with //K<sub>a</sub>// = 0 and 1 were detected near 43 GHz with the 100 m GBT.		The three //J// = 16 – 15 transitions with //K<sub>a</sub>// = 0 and 1 were detected near 43 GHz with the 100 m GBT.
Line 18:		Line 18:

	Contributor(s): H. S. P. Müller; 08, 2012; 10, 2017		Contributor(s): H. S. P. Müller; 08, 2012; 10, 2017
-

	----		----

c6h3n

anonymous@undisclosed.example.com (Anonymous) — Fri, 22 Jul 2022 12:22:12 +0000

2022/07/22 14:19		current
Line 10:		Line 10:
	R. Fuentetaja, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, J. R. Pardo, P. de Vicente, and J. Cernicharo\\		R. Fuentetaja, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, J. R. Pardo, P. de Vicente, and J. Cernicharo\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1051/0004-6361/202243857\|Discovery of CH<sub>2</sub>CCHC<sub>4</sub>H and a Rigorous Detection of H<sub>2</sub>CCCHC<sub>3</sub>N in TMC-1 with the QUIJOTE Line Survey]]\\	+	[[https://doi.org/10.1051/0004-6361/202243857\|Discovery of CH<sub>2</sub>CCHC<sub>4</sub>H and a Rigorous Detection of CH<sub>2</sub>CCHC<sub>3</sub>N in TMC-1 with the QUIJOTE Line Survey]]\\
	//Astron. Astrophys.// 663, Art. No. L3 (2022).\\		//Astron. Astrophys.// 663, Art. No. L3 (2022).\\
-	H<sub>2</sub>CCCHC<sub>3</sub>N was identified in TMC-1 for the first time through individual lines. The H<sub>2</sub>CCHC<sub>4</sub>H to H<sub>2</sub>CCCHC<sub>3</sub>N ratio was determined as 18 ± 4, somewhat higher than the C<sub>4</sub>H to C<sub>3</sub>N ratio of ~8.\\	+	H<sub>2</sub>CCCHC<sub>3</sub>N was identified in TMC-1 for the first time through individual lines. The H<sub>2</sub>CCCHC<sub>4</sub>H to H<sub>2</sub>CCCHC<sub>3</sub>N ratio was determined as 18 ± 4, somewhat higher than the C<sub>4</sub>H to C<sub>3</sub>N ratio of ~8.\\
	\\		\\

c7h

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:39:04 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	The heptatriynylidyne radical in its <sup>2</sup>Π<sub>r</sub> state has been detected with the IRAM 30 M telescope in five lines of three rotational transitions toward the nearby C-rich AGB star CW Leonis by\\		The heptatriynylidyne radical in its <sup>2</sup>Π<sub>r</sub> state has been detected with the IRAM 30 M telescope in five lines of three rotational transitions toward the nearby C-rich AGB star CW Leonis by\\
	M. Guélin, J. Cernicharo, M. J. Travers, M. C. McCarthy, C. A. Gottlieb, P. Thaddeus, M. Ohishi, S. Saito, and S. Yamamoto,\\		M. Guélin, J. Cernicharo, M. J. Travers, M. C. McCarthy, C. A. Gottlieb, P. Thaddeus, M. Ohishi, S. Saito, and S. Yamamoto,\\
-	[[http://cdsads.u-strasbg.fr/abs/1997A%26A...317L...1G\|Detection of a new Linear Carbon Chain Radical: C<sub>7</sub>H]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1997A%26A...317L...1G\|Detection of a new Linear Carbon Chain Radical: C<sub>7</sub>H]],\\
	//Astron. Astrophys.// 317 L1–L4 (1997).\\		//Astron. Astrophys.// 317 L1–L4 (1997).\\
	The //J// = 47.5 – 46.5, 48.5 – 47.5, and half of the 49.5 – 48.5 were detected betwen 83.0 and 86.6 GHz.		The //J// = 47.5 – 46.5, 48.5 – 47.5, and half of the 49.5 – 48.5 were detected betwen 83.0 and 86.6 GHz.
Line 9:		Line 9:
	M. Araki, S. Takano, N. Sakai, S. Yamamoto, T. Oyama, N. Kuze, and K. Tsukiyama\\		M. Araki, S. Takano, N. Sakai, S. Yamamoto, T. Oyama, N. Kuze, and K. Tsukiyama\\
	reported on\\		reported on\\
-	[[http://dx.doi.org/10.3847/1538-4357/aa8637\|Long Carbon Chains in the Warm Carbon-chain-chemistry Source L1527: First Detection of C<sub>7</sub>H in Molecular Clouds]],\\	+	[[https://doi.org/10.3847/1538-4357/aa8637\|Long Carbon Chains in the Warm Carbon-chain-chemistry Source L1527: First Detection of C<sub>7</sub>H in Molecular Clouds]],\\
	//Astrophys. J.// 847 Art. No. 51 (2017).\\		//Astrophys. J.// 847 Art. No. 51 (2017).\\
	Using the 100 m GBT, four Λ-components of the two transitions with //J// = 24.5 – 23.5 and 25.5 – 24.5 near 42.85 and 44.60 GHz were detected barely to reasonably well; a composite spectrum is beyond doubt.		Using the 100 m GBT, four Λ-components of the two transitions with //J// = 24.5 – 23.5 and 25.5 – 24.5 near 42.85 and 44.60 GHz were detected barely to reasonably well; a composite spectrum is beyond doubt.
Line 17:		Line 17:

	Contributor(s): H. S. P. Müller; 05, 2007; 10, 2017		Contributor(s): H. S. P. Müller; 05, 2007; 10, 2017
-

	----		----

c7h4

anonymous@undisclosed.example.com (Anonymous) — Fri, 22 Jul 2022 12:17:46 +0000

2022/07/22 14:03		current
Line 1:		Line 1:
	===== On C7H4 Isomers in the Interstellar Medium =====		===== On C7H4 Isomers in the Interstellar Medium =====

-	R. Fuentetaja, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, J. R. Pardo, P. de Vicente, and J. Cernicharo\\	+	R. Fuentetaja, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, J. R. Pardo, P. de Vicente, and J. Cernicharo\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.1051/0004-6361/202243857\|Discovery of CH<sub>2</sub>CCHC<sub>4</sub>H and a Rigorous Detection of H<sub>2</sub>CCCHC<sub>3</sub>N in TMC-1 with the QUIJOTE Line Survey]]\\		[[https://doi.org/10.1051/0004-6361/202243857\|Discovery of CH<sub>2</sub>CCHC<sub>4</sub>H and a Rigorous Detection of H<sub>2</sub>CCCHC<sub>3</sub>N in TMC-1 with the QUIJOTE Line Survey]]\\
	//Astron. Astrophys.// 663, Art. No. L3 (2022).\\		//Astron. Astrophys.// 663, Art. No. L3 (2022).\\
-	1,2-Heptadiene-4,6-diyne, also known as propadienylbutadiyne or allenyldiacetylene, was detected with the Yebes 40 m radio telescope between 31.2 and 43.0 GHz. 21 lines with 16 ≤ //J// ≤ 22 and //K<sub>a</sub>// ≤ 2 were identified as being between unblended and not completely blended.	+	1,2-Heptadiene-4,6-diyne, also known as propadienylbutadiyne or allenyldiacetylene, was detected with the Yebes 40 m radio telescope between 31.2 and 43.0 GHz. 21 lines with 16 ≤ //J// ≤ 22 and //K<sub>a</sub>// ≤ 2 were identified as being between unblended and not completely blended. //T//<sub>rot</sub> was determined as 9.0 ± 0.5 K. The isoelectronic H<sub>2</sub>CCCHC<sub>3</sub>N was identified in TMC-1 for the first time through individual lines. The CH<sub>2</sub>CCHC<sub>4</sub>H to H<sub>2</sub>CCCHC<sub>3</sub>N ratio was determined as 18 ± 4, somewhat higher than the C<sub>4</sub>H to C<sub>3</sub>N ratio of ~8. Similarly, the CH<sub>3</sub>C<sub>6</sub>H to CH<sub>2</sub>CCHC<sub>4</sub>H ratio is ~0.32, whereas the CH<sub>3</sub>C<sub>4</sub>H to CH<sub>2</sub>CCHC<sub>2</sub>H ratio is ~1.1.\\
-	The molecule has a column density about a factor of 60 lower than that of acetyleneallene. This ratio is similar to that of other pairs of unsaturated hydrocarbons on one hand and cyano derivatives of these on the other.\\	+	\\

	----		----

c7n

anonymous@undisclosed.example.com (Anonymous) — Mon, 20 Feb 2023 13:14:53 +0000

2023/02/20 14:06		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202245816\|Discovery of the C<sub>7</sub>N<sup>−</sup> Anion in TMC-1 and IRC +10216]]\\		[[https://doi.org/10.1051/0004-6361/202245816\|Discovery of the C<sub>7</sub>N<sup>−</sup> Anion in TMC-1 and IRC +10216]]\\
	//Astron. Astrophys.// 670, (2023), Art. No. L19.\\		//Astron. Astrophys.// 670, (2023), Art. No. L19.\\
-	Six transitions with 26 ≤ //J"// ≤ 31 and 17 transitions with 26 ≤ //J"// ≤ 42 were detected toward the dark cloud TMC-1 and the C-rich late-type star CW Leonis, respectively, in the course of two molecular line surveys.	+	Six transitions with 26 ≤ //J"// ≤ 31 and 17 transitions with 26 ≤ //J"// ≤ 42 were detected toward the dark cloud TMC-1 and the C-rich late-type star CW Leonis, respectively, in the course of two molecular line surveys. The identification relies on quantum-chemical observations as no laboraotory data exist to date, as in the case of C<sub>5</sub>N<sup>−</sup>. The rotational temperature //T//<sub>rot</sub> was fit as 6.0 ± 0.5 K in TMC-1 and as 26.6 ± 1.8 K toward CW Leonis; both values are similar to those of C<sub>5</sub>N<sup>−</sup>. The C<sub>5</sub>N<sup>−</sup> to C<sub>7</sub>N<sup>−</sup> in TMC-1 is ~5, toward CW Leonis ~2.4.\\
		+	\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 02, 2023
		+
		+	----
		+

c8h-minus

anonymous@undisclosed.example.com (Anonymous) — Mon, 27 Feb 2023 12:26:04 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	The octatetraynylide ion has been detected toward the dark cloud TMC-1 in four rotational transitions between 24 and 16 mm:\\		The octatetraynylide ion has been detected toward the dark cloud TMC-1 in four rotational transitions between 24 and 16 mm:\\
	S. Brünken, H. Gupta, C. A. Gottlieb, M. C. McCarthy, and P. Thaddeus,\\		S. Brünken, H. Gupta, C. A. Gottlieb, M. C. McCarthy, and P. Thaddeus,\\
-	[[http://dx.doi.org/10.1086/520703\|Detection of the Carbon Chain Negative Ion C<sub>8</sub>H<sup>–</sup> in TMC-1]]\\	+	[[https://doi.org/10.1086/520703\|Detection of the Carbon Chain Negative Ion C<sub>8</sub>H<sup>–</sup> in TMC-1]]\\
	//Astrophys. J.// 664, L43–L46 (2007).\\		//Astrophys. J.// 664, L43–L46 (2007).\\
	At almost the same time it had been detected in observations toward the carbon rich star IRC +10216 in 5 rotational transitions occuring at 12 and around 7 mm:\\		At almost the same time it had been detected in observations toward the carbon rich star IRC +10216 in 5 rotational transitions occuring at 12 and around 7 mm:\\
	A. J. Remijan, J. M. Hollis, F. J. Lovas, M. A. Cordiner, T. J. Millar, A. J. Markwick-Kemper, and P. R. Jewell,\\		A. J. Remijan, J. M. Hollis, F. J. Lovas, M. A. Cordiner, T. J. Millar, A. J. Markwick-Kemper, and P. R. Jewell,\\
-	[[http://dx.doi.org/10.1086/520704\|Detection of C<sub>8</sub>H<sup>–</sup> and Comparison with C<sub>8</sub>H toward IRC +10216]]\\	+	[[https://doi.org/10.1086/520704\|Detection of C<sub>8</sub>H<sup>–</sup> and Comparison with C<sub>8</sub>H toward IRC +10216]]\\
-	//Astrophys. J.// 664, L47–L50 (2007).	+	//Astrophys. J.// 664, L47–L50 (2007).\\
		+	\\

	----		----

	Contributor(s): H. S. P. Müller; 7, 2007		Contributor(s): H. S. P. Müller; 7, 2007
-

	----		----

c8h

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:49:29 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	Even the octatetraynyl radical in its <sup>2</sup>Π<sub>3/2</sub> lower spin component has been detected in ten rotational transitions toward IRC +10216 by\\		Even the octatetraynyl radical in its <sup>2</sup>Π<sub>3/2</sub> lower spin component has been detected in ten rotational transitions toward IRC +10216 by\\
	J. Cernicharo, and M. Guélin,\\		J. Cernicharo, and M. Guélin,\\
-	[[http://cdsads.u-strasbg.fr/abs/1996A%26A...309L..27C\|Discovery of the C<sub>8</sub>H Radical]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1996A%26A...309L..27C\|Discovery of the C<sub>8</sub>H Radical]],\\
	//Astron. Astrophys.// 309 L27–L30 (1996)\\		//Astron. Astrophys.// 309 L27–L30 (1996)\\
	before it was actually detected in the laboratory.		before it was actually detected in the laboratory.
Line 9:		Line 9:
	Later, it was also identified in TMC-1 by observing four lines of two rotational transitions:\\		Later, it was also identified in TMC-1 by observing four lines of two rotational transitions:\\
	M. B. Bell, P. A. Feldman, J. K. G. Watson, M. C. McCarthy, M. J. Travers, C. A. Gottlieb, and P. Thaddeus,\\		M. B. Bell, P. A. Feldman, J. K. G. Watson, M. C. McCarthy, M. J. Travers, C. A. Gottlieb, and P. Thaddeus,\\
-	[[http://dx.doi.org/10.1086/307303\|Observations of Long C<sub>n</sub>H Molecules in the Dust Cloud TMC-1]],\\	+	[[https://doi.org/10.1086/307303\|Observations of Long C<sub>n</sub>H Molecules in the Dust Cloud TMC-1]],\\
	//Astrophys. J.// 518 740–747 (1999).		//Astrophys. J.// 518 740–747 (1999).

Line 16:		Line 16:

	Contributor(s): H. S. P. Müller; 05, 2007		Contributor(s): H. S. P. Müller; 05, 2007
-

	----		----

c10h

anonymous@undisclosed.example.com (Anonymous) — Mon, 04 Sep 2023 13:13:01 +0000

2023/02/27 13:11		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/acb648\|Astronomical Detection of the Interstellar Anion C<sub>10</sub>H<sup>–</sup> toward TMC-1 from the GOTHAM Large Program on the Green Bank Telescope]]\\		[[https://doi.org/10.3847/2041-8213/acb648\|Astronomical Detection of the Interstellar Anion C<sub>10</sub>H<sup>–</sup> toward TMC-1 from the GOTHAM Large Program on the Green Bank Telescope]]\\
	//Astrophys. J. Lett.// 944, Art. No. L45 (2023).\\		//Astrophys. J. Lett.// 944, Art. No. L45 (2023).\\
		+	The identification was made by stacking data from the line survey up to 30 GHz; most signal-contribution came from the 13.1 to 19.2 GHz region. The authors also report a tentative detection of C<sub>10</sub>H with a C<sub>10</sub>H<sup>–</sup> to C<sub>10</sub>H of roughly 2. In addition, C<sub>10</sub>H<sup>–</sup> is roughly 5 times more abundant than C<sub>8</sub>H<sup>–</sup> and about one third more abundant than C<sub>6</sub>H<sup>–</sup>.\\
		+	\\
		+
		+	More recently,\\
		+	J. R. Pardo, C. Cabezas, M. Agúndez, B. Tercero, N. Marcelino, P. de Vicente, M. Guélin, and J. Cernicharo\\
		+	found\\
		+	[[https://doi.org/10.1051/0004-6361/202346498\|A new heavy anion in IRC+10216: Theory favors C10H− versus C9N−]]\\
		+	//Astron. Astrophys.// 677, Art. No. A55 (2023).\\
		+	This time around, the molecule was identified in 15 not or not strongly blended transitions with 51 ≤ //J// ≤ 71 between 31 and 43 GHz in the course of a molecular line survey of the famous carbon rich AGB star CW Leonis carried out with the Yebes 40 m radio telescope.\\
		+
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 02, 2023; 09, 2023
		+
		+	----
		+
		+

c60-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 24 Apr 2019 13:31:09 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== C60+ in the ISM =====
	+
	+	B. H. Foing and P. Ehrenfreund,\\
	+	reported on the\\
	+	[[https://doi.org/10.1038/369296a0\|Detection of two Interstellar Absorption Bands Coincident with Spectral Features of C<sub>60</sub><sup>+</sup>]]\\
	+	//Nature// 369, 296 (1994).\\
	+	Two weak diffuse interstellar bands at 963.2 and 957.7 nm were detected in absoption toward several reddened stars. The were assigned to C<sub>60</sub><sup>+</sup> on the basis of laboratory electronic spectra of the molecular catio isolated in neon matrix. These features were blue-shifted less than 0.1 % from the strongest matrix bands. Even though the level of agreement is in the normal range, the identification was not beyond doubt.
	+
	+	J. Fulara, M. Jakobi, and J. P. Maier,\\
	+	reported on\\
	+	[[https://doi.org/10.1016/0009-2614(93)85190-Y\|Electronic and Infrared Spectra of C<sub>60</sub><sup>+</sup> and C<sub>60</sub><sup>–</sup> in Neon and Argon Matrices]]\\
	+	//Chem. Phys. Lett.// 211, 227 (1993).
	+
	+	Very recently, E. K. Campbell, M. Holz, D. Gerlich, and J. P. Maier,\\
	+	reported on the\\
	+	[[https://doi.org/10.1038/nature14566\|Laboratory Confirmation of C<sub>60</sub><sup>+</sup> as the Carrier of Two Diffuse Interstellar Bands]]\\
	+	//Nature// 523, 322 (2015).\\
	+	The authors determined gas phase wavelengths of two strong electronic absorption features of C<sub>60</sub><sup>+</sup> (957.75 and 963.27 nm), but also for two weaker ones (942.85 and 936.59 nm).
	+
	+	Finally, G. A. H. Walker, D. A. Bohlender, J. P. Maier, and E. K. Campbell,\\
	+	reported on the\\
	+	[[https://doi.org/10.1088/2041-8205/812/1/L8\|Identification of More Interstellar C<sub>60</sub><sup>+</sup> Bands]]\\
	+	//Astrophys. J.// 812, Art. No. L8 (2015).\\
	+	In fact, the authors detected the two weaker features toward the stars HD 183143 and HD 169454, the latter from archival data. This detection dispels any possibly remaining doubt on the detection of this molecular cation.
	+
	+	Meanwhile, S. Iglesias-Groth and M. Esposito,\\
	+	reported on the\\
	+	[[https://doi.org/10.1088/2041-8205/776/1/L2\|A Search for near Infrared Bands of the Fullerene Cation C<sub>60</sub><sup>+</sup> in the Protoplanetary Nebula IRAS 01005+7910]]\\
	+	//Astrophys. J.// 776, Art. No. L2 (2013).\\
	+	The authors detected the two stronger features in absorption.
	+
	+	Before, O. Berné, G. Mulas, and C. Joblin,\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/201220730\|Interstellar C<sub>60</sub><sup>+</sup>]]\\
	+	//Astron. Astrophys.// 550, Art. No. L4 (2013).\\
	+	Severeal weak infrared emission features detected in a specific position of the reflection nebula NGC 7023 were assigned to stronger bands of C<sub>60</sub><sup>+</sup> based on comparsion with matrix IR spectra.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2015
	+
	+
	+	----
	+

cac2

anonymous@undisclosed.example.com (Anonymous) — Thu, 16 May 2024 14:00:46 +0000

2024/05/16 15:35		current
Line 6:		Line 6:
	[[https://doi.org/10.3847/2041-8213/ad3336\|Calcium Chemistry in Carbon-rich Circumstellar Environments: The Laboratory and Astronomical Discovery of Calcium Dicarbide, CaC<sub>2</sub>]]\\		[[https://doi.org/10.3847/2041-8213/ad3336\|Calcium Chemistry in Carbon-rich Circumstellar Environments: The Laboratory and Astronomical Discovery of Calcium Dicarbide, CaC<sub>2</sub>]]\\
	//Astrophys. J. Lett// 966, Art. No. L28 (2024).\\		//Astrophys. J. Lett// 966, Art. No. L28 (2024).\\
-	Ten //a//-type lines with 1 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 4 between 41 and 150 GHz were identified for the main <sup>24</sup>Mg isotopolog employing the Yebes 40 m and IRAM 30 m dishes in the couses of molecular line surveys of CW Leonis. These lines have good to reasonable signal-to-noise ratios, and several lines are unblended. One and three lines were identified for the <sup>25</sup>Mg and <sup>26</sup>Mg minor isotopologs, respectively. The isotopic ratios are compatible with solar values within uncertainties. The derived MgC<sub>2</sub> : MgC<sub>2</sub>H : MgC<sub>4</sub>H : MgC<sub>6</sub>H abundance raios are about 1 : 2 : 22 : 20.\\	+	14 //a//-type lines with 0 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 4 between 14 and 115 GHz were identified for the main <sup>40</sup>Ca isotopolog employing the GBT 100 m, Yebes 40 m, and IRAM 30 m dishes. The observations with the GBT were dedicated ones, the other results were obtained in the couses of molecular line surveys of CW Leonis. These lines have good to reasonable signal-to-noise ratios, and several lines are unblended. Transitions of minor isotopologs were not identified. The derived column density ratio of MgC<sub>2</sub>/CaC<sub>2</sub> is roughly 2.\\
	\\		\\

canc

anonymous@undisclosed.example.com (Anonymous) — Tue, 09 Jul 2019 14:33:09 +0000

2019/07/09 16:21		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/201936040\|Discovery of the First Ca-bearing molecule in Space: CaNC]]\\		[[https://doi.org/10.1051/0004-6361/201936040\|Discovery of the First Ca-bearing molecule in Space: CaNC]]\\
	//Astron. Astrophys.// 627, Art. No. L4 (2019).\\		//Astron. Astrophys.// 627, Art. No. L4 (2019).\\
		+	Nine rotational transitions with //N// = 9 − 8 to 21 − 20 were observed in emission between 72.8 and 169.9 GHz using the IRAM 30 m telecope. One transition is severely blended, a few others slightly to considerably. In addition, the signal-to-noise ratio is poor for some transitions, but reasonable for many. All transitions display fine structure splitting, and each of the FS components has U-shape typical for envelope species. The molecule is about 60 times less abundant than the lighter homolog MgNC and about similar abundant as FeCN in this source.\\
		+
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 07, 2019
		+
		+
		+	----
		+

cco

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:19:11 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Oxoethenylidene, CCO, in the ISM =====
	+
	+	CCO has been detected first toward TMC-1:\\
	+	M. Ohishi, H. Suzuki, S.-I. Ishikawa, C. Yamada, H. Kanamori, W. M. Irvine, R. D. Brown, P. D. Godfrey, N. Kaifu,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1991ApJ...380L..39O\|Detection of a new carbon-chain molecule, CCO]]\\
	+	//Astrophys. J.// 380, L39–L42 (1991).\\
	+	The //N<sub>J</sub>// = 1<sub>2</sub> – 0<sub>1</sub> and 2<sub>3</sub> – 1<sub>2</sub> transitions werev detected with the 43 m Green Bank telescope and the 45 m Nobeyama telecope, respectively, at 22258 and 45827 MHz.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2003; 09, 2012
	+
	+
	+	----
	+

ccp

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:38:28 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of the Phosphapropynylidyne Radical, CCP, toward IRC +10216 =====
	+
	+	The phosphapropynylidyne radical, CCP, has been detected in five lines of four rotational transitions in the 3 and 2 mm regions:\\
	+	D. T. Halfen, D. J. Clouthier, and L. M. Ziurys,\\
	+	[[https://doi.org/10.1086/588024\|Detection of the CCP Radical (X <sup>2</sup>Π<sub>r</sub>) in IRC +10216: A New Interstellar Phosphorus-containing Species]]\\
	+	//Astrophys. J.// 677, L101–L104 (2008).\\
	+	The //e// λ-doubling component is overlapped by stronger featueres for the first three transitions; the //f// component seems to be unaffected for all four transitions.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 03, 2008
	+
	+	----
	+

cf-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:02:04 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Fluoromethylidynium =====
	+
	+	Fluoromethylidynium, CF<sup>+</sup>, may seem like an odd molecule. However, it is isoelectronic to CO with a similar rotational constant, but a dipole moment that is about ten times larger. Its detection toward the PDR Orion-Bar was reported by\\
	+	D. A. Neufeld, P. Schilke, K. M. Menten, M. G. Wolfire, J. H. Black, F. Schuller, H. S. P. Müller, S. Thorwirth, R. Güsten, and S. Philipp,\\
	+	[[https://doi.org/10.1051/0004-6361:200600015\|Discovery of Interstellar CF<sup>+</sup>]]\\
	+	//Astron. Astrophys.// 454, L37–L40 (2006).\\
	+	The //J// = 1 – 0 and 2 – 1 transitions were detected with the IRAM 30 m telescope at 102.6 and 205.2 GHz, respectively, as well as the 3 – 2 transition with the APEX 12 m dish at 307.7 GHz.
	+
	+	The //J// = 1 – 0 transition was also detected in two 3 mm molecular line surveys carried out with the 20 m OSO telescope:\\
	+	[[https://doi.org/10.1134/S1063772910040037\|Spectral scan of the star-forming region DR21(OH). Observations and LTE analysis]]\\
	+	//Astron. Rep.// 54, 295–316 (2010);\\
	+	[[https://doi.org/10.1134/S1063772910120036\|Spectral survey of the star-forming region W51 e1/e2 at 3 mm]]\\
	+	//Astron. Rep.// 54, 1084–1104 (2010);\\
	+	both by S. V. Kalenskii and by L. E. B. Johansson.\\
	+	Details in the second article are more limited than in the first one. Because of the observation of only one line, the identifications were viewed somewhat tentatively. Nevertheless, the observation of HCO indicates PDR activity in the regions observed.
	+
	+	The more recent detection of the //J// = 1 – 0 and 2 – 1 transitions by\\
	+	V. Guzmán, J. Pety, P. Gratier, J. R. Goicoechea, M. Gerin, E. Roueff, and D. Teyssier,\\
	+	**[[https://doi.org/10.1051/0004-6361/201219449\|The IRAM-30m line survey of the Horsehead PDR\\
	+	I. CF<sup>+</sup> as a tracer of C<sup>+</sup> and as a measure of the fluorine abundance]]**\\
	+	//Astron. Astrophys.// 543, Art. No. 1 (2012);\\
	+	suggests that the cation is a fairly common PDR molecule. It is worthwhile mentioning that the line width in this source was particularly narrow that the 1 – 0 transition displayed <sup>19</sup>F nuclear spin-rotation splitting.
	+
	+	H. S. Liszt, J. Pety, M. Gerin, and R. Lucas,\\
	+	detected with the IRAM 30 m telescope\\
	+	[[https://doi.org/10.1051/0004-6361/201323320\|HCO, //c//-C<sub>3</sub>H and CF<sup>+</sup>: three new molecules in diffuse, translucent and “spiral-arm” clouds]]\\
	+	//Astron. Astrophys.// 564, Art. No. A64 (2014).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 09, 2005; 08, 2006; 11, 2012; 05, 2015
	+
	+	----
	+

ch-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 14 Jul 2021 08:58:58 +0000

2021/07/14 10:44		current
Line 55:		Line 55:
	[[https://doi.org/10.1051/0004-6361/202040203\|//Herschel// observations of EXtraOrdinary Sources: Full //Herschel///HIFI Molecular Line Survey of Sagittarius B2(M)]]\\		[[https://doi.org/10.1051/0004-6361/202040203\|//Herschel// observations of EXtraOrdinary Sources: Full //Herschel///HIFI Molecular Line Survey of Sagittarius B2(M)]]\\
	//Astron. Astrophys.// 651, Art. No. A9 (2021).\\		//Astron. Astrophys.// 651, Art. No. A9 (2021).\\
-	They observe clearly the //J// = 2 − 1 transition of CD<sup>+</sup> near 906.8 GHz mostly in absorption. The //J// = 4 − 2 transition near 1811.2 GHz is seen weakly in absorption.\\	+	They observed clearly the //J// = 2 − 1 transition of CD<sup>+</sup> near 906.8 GHz mostly in absorption. The //J// = 4 − 2 transition near 1811.2 GHz is seen weakly in absorption.\\


	----		----

-	Contributor(s): H. S. P. Müller; 2003; 02, 2006; 03, 2007; 04, 2011; 05, 2020; 07, 2021	+	Contributor(s): H. S. P. Müller; 2003; 02, 2006; 03, 2007; 04, 2011; 05, 2020; 07, 2021.

	----		----

ch2

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:21:24 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of the CH2 in the ISM =====
	+
	+	The methylene radical CH<sub>2</sub> had been identified in spectra recorded toward Orion KL and W51 M:\\
	+	J. M. Hollis, P. R. Jewell, and F. J. Lovas,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1995ApJ...438..259H\|Confirmation of Interstellar Methylene]]\\
	+	//Astrophys.// 438, 259–264 (1995).\\
	+	Even though only one transition was detected, namely the //N<sub>K<sub>a</sub>,K<sub>c</sub></sub>// = 4<sub>0,4</sub> – 3<sub>1,3</sub> transition, the observation of resolved fine and hyperfine structure secures the detection. It is noteworthy to point out that this transition probes fairly hot methylene; the transition is more than 200 K above ground.
	+
	+	More recently, cold methylene has been detected in absorption toward Sgr B2 and W49 N. The transitions had been recorded earlier with the ISO Long Wavelength Spectrometer:\\
	+	E. T. Polehampton, K. M. Menten, S. Brünken, G. Winnewisser, and J.-P. Baluteau\\
	+	[[https://doi.org/10.1051/0004-6361:20041598\|Far-Infrared Detection of Methylene]]\\
	+	//Astron. Astrophys.// 431, 203–213 (2005).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 02, 2006
	+
	+
	+	----
	+

ch3-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 30 Dec 2025 10:42:56 +0000

2025/12/30 11:36		current
Line 28:		Line 28:
	\\		\\

		+	C. Bhatt, J. Cami, E. Peeters, N. Clark, P. Moraga Baez, K. Volk, G. C. Sloan, J. H. Kastner, H. L. Dinerstein, M. Matsuura, B. Balick, K. E. Kraemer, K. Justtanont, O. Jones, R. Sahai, I. Aleman, M. J. Barlow, J. Bernard-Salas, J. Blommaert, N. Hirano, P. Kavanagh, F. Kemper, E. Lagadec, J. M. Laming, F. Molster, H. Monteiro, A. M. S. Richards, N. C. Sterling, M. Torki, P. A. M. van Hoof, J. R. Walsh, L. B. F. M. Waters, R. Wesson, F. Wilson, N. J. Wright, and A. A. Zijlstra\\
		+	reported more recently on\\
		+	[[https://doi.org/10.3847/1538-4357/ae1020\|Detection of CH3+ in the O-rich Planetary Nebula NGC 6302]]\\
		+	//Astrophys. J.// 995, Art. No. 67 (2025).\\
		+	\\

	----		----

ch3c4h

anonymous@undisclosed.example.com (Anonymous) — Fri, 28 Nov 2025 12:27:29 +0000

2025/11/28 13:18		current
Line 30:		Line 30:
	[[https://doi.org/10.1051/202557754\|Detection of Six Isotopologues of CH<sub>3</sub>CCCCH in TMC-1 with the QUIJOTE Line Survey]],\\		[[https://doi.org/10.1051/202557754\|Detection of Six Isotopologues of CH<sub>3</sub>CCCCH in TMC-1 with the QUIJOTE Line Survey]],\\
	//Astron. Astrophys.// 703 Art. No. L22 (2025).\\		//Astron. Astrophys.// 703 Art. No. L22 (2025).\\
-		+	With an increase of the signal-to-noise ratio in comparison to the previous item, the authors were able to identify transition with //J// = 8 to 12 and //K<sub>a</sub>// ≤ 1 of all five singly substituted <sup>13</sup>C isotopologs and of CH<sub>3</sub>C<sub>4</sub>D with reasonable to good S/N and mostly not or only slightly blended. The lowest //J// pair of CH<sub>3</sub>C<sub>4</sub>D transitions was not covered. The <sup>12</sup>C/<sup>13</sup>C ratio is 93 ± 11, while the H/D ratio in the case of CH<sub>3</sub>C<sub>4</sub>D is 54 ± 8.\\
		+	\\

	----		----

ch3c6h

anonymous@undisclosed.example.com (Anonymous) — Wed, 24 Apr 2019 14:15:59 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on the Detection of 1,3,5-Heptatriyne in the ISM =====
	+
	+	The 1,3,5-heptatriyne molecule CH<sub>3</sub>C<sub>6</sub>H, aka methyltriacetylene, has been identified in spectra recorded toward TMC-1 by\\
	+	A. R. Remijan, J. M. Hollis, L. E. Snyder, P. R. Jewell, and F. J. Lovas,\\
	+	[[https://doi.org/10.1086/504918\|Methyltriacetylene (CH<sub>3</sub>C<sub>6</sub>H) toward TMC-1: Presently the Largest Detected Symmetric Top]]\\
	+	//Astrophys. J.// 643, L37–L40 (2006).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 4, 2006
	+
	+
	+	----
	+

ch3chco

anonymous@undisclosed.example.com (Anonymous) — Mon, 06 Mar 2023 11:20:04 +0000

2023/03/06 12:08		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202245732\|Discovery of CH<sub>3</sub>CHCO in TMC-1 with the QUIJOTE Line Survey]]\\		[[https://doi.org/10.1051/0004-6361/202245732\|Discovery of CH<sub>3</sub>CHCO in TMC-1 with the QUIJOTE Line Survey]]\\
	//Astron. Astrophys.// 671, (2023), Art. No. L6.\\		//Astron. Astrophys.// 671, (2023), Art. No. L6.\\
		+	Ten rotational transitions with 3 ≤ //J// ≤ 5 and //K<sub>a</sub>// were identified with resolved methyl internal rotation splitting. A sufficiently large fraction of the lines is not or only marginally blended and above the 3//σ// noise level. The ketene to methylketene ratio is ~93; the ratio of methylketene to it isomer //trans//-propenal is about 2/3.\\
		+	\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 03, 2023
		+
		+	----
		+

ch3chs

anonymous@undisclosed.example.com (Anonymous) — Thu, 30 Jan 2025 14:35:13 +0000

2025/01/30 15:26		current
Line 3:		Line 3:
	M. Agúndez, G. Molpeceres, C. Cabezas, N. Marcelino, B. Tercero, R. Fuentetaja, P. de Vicente, and J. Cernicharo\\		M. Agúndez, G. Molpeceres, C. Cabezas, N. Marcelino, B. Tercero, R. Fuentetaja, P. de Vicente, and J. Cernicharo\\
	announced the\\		announced the\\
-	[[https://doi.org/10.1051/0004-6361/202142156\|Discovery of Interstellar 3-Cyanopropargyl Radical, CH<sub>2</sub>CCCN]]\\	+	[[https://doi.org/10.1051/0004-6361/202453459\|Detection of Thioacetaldehyde (CH<sub>3</sub>CHS) in TMC-1: Sulfur-oxygen Differentiation along the Hydrogenation Sequence]]\\
-	//Astron. Astrophys.// **654, Art. No. L9 (2021**).\\	+	//Astron. Astrophys.// **693, Art. No. L20 (2025**).\\
-	//ortho//-CH<sub>2</sub>C<sub>3</sub>N was identified through three //a//-type transitions with //J// = 8 − 7 to 10 − 9 and //K<sub>a</sub>// = 0 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. These transitions displayed partially resolved fine and hyperfine structure splitting; few components were blended by lines of other species. Also observed were four transitions of //para//-CH<sub>2</sub>C<sub>3</sub>N with //J// = 8 − 7 or 9 − 8 and //K<sub>a</sub>// = 1, which displayed well resolved fine structure splitting; some of these lines were also blended. A value of //T//<sub>rot</sub> = 7 ± 1 K was derived. The column density of CH<sub>2</sub>C<sub>3</sub>N is about a factor of 100 lower than that of CH<sub>2</sub>CN. And while CH<sub>2</sub>C<sub>3</sub>N is roughly a factor of 10 less abundant than CH<sub>3</sub>C<sub>3</sub>N, CH<sub>2</sub>CN is more abundant than CH<sub>3</sub>CN by a factor of about 3.\\	+	Thioacetaldehyde, also known as ethanthial, was identified through four //a//-type transitions with //J// = 3 − 2 and 4 − 3 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. The transitions displayed resolved methyl internal rotation splitting; the E component of 3<sub>03</sub> − 2<sub>02</sub> is blended. A value of //T//<sub>rot</sub> = 9 K was assumed. Its column density is about a factor of 36 lower than that of acetaldehyde.\\
	\\		\\

ch3co

anonymous@undisclosed.example.com (Anonymous) — Fri, 26 Feb 2021 15:36:30 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Methyloxomethylium, CH3CO+, in the ISM =====
	+
	+	J. Cernicharo, C. Cabezas, S. Bailleux, L. Margulès, R. Motiyenko, L. Zou, Y. Endo, C. Bermúdez, M. Agúndez, N. Marcelino, B. Lefloch, B. Tercero, and P. de Vicente\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/202040076\|Discovery of the acetyl cation, CH<sub>3</sub>CO<sup>+</sup>, in space and in the laboratory]]\\
	+	//Astron Astrophys.// 646, Art. No. L7 (2021).\\
	+	Eight transitions with //J'// = 2, 4, 5, and 6 and with //K// = 0 and 1 were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m and the IRAM 30 m radio telescopes. The molecule was also identified in the cold dense cores L483, L1527, and L1544.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller 02, 2021
	+
	+	----
	+

ch3oh

anonymous@undisclosed.example.com (Anonymous) — Mon, 09 Feb 2026 11:14:29 +0000

2026/02/09 11:58		current
Line 70:		Line 70:
	H. S. P. Müller, V. V. Ilyushin, A. Belloche, F. Lewen, and S. Schlemmer\\		H. S. P. Müller, V. V. Ilyushin, A. Belloche, F. Lewen, and S. Schlemmer\\
	reported on an\\		reported on an\\
-	[[https://doi.org/10.1051/0004-6361/202451011\|Investigation of the Rotational Spectrum of CH<sub>3</sub><sup>17</sup>OH and its Tentative Detection toward Sagittarius B2(N)]]\\	+	[[https://doi.org/10.1051/0004-6361/202451011\|Investigation of the Rotational Spectrum of CH3(17)OH and its Tentative Detection toward Sagittarius B2(N)]]\\
	//Astron. Astrophys.// 688, Art. No. A201 (2024).\\		//Astron. Astrophys.// 688, Art. No. A201 (2024).\\
	The authors report a tentative detection of this isotopolog in the ReExploring Molecular Complexity with ALMA survey at 3 mm. Only one unblended and one partially blended line were identified, many more were severely bleded or too weak. The derived CH<sub>3</sub><sup>18</sup>OH to CH<sub>3</sub><sup>17</sup>OH ratio of ~3.3 is along <sup>18</sup>O to <sup>17</sup>O ratios found for other molecules in the Galactic Center as is the CH<sub>3</sub><sup>16</sup>OH to CH<sub>3</sub><sup>18</sup>OH ratio of 240.\\		The authors report a tentative detection of this isotopolog in the ReExploring Molecular Complexity with ALMA survey at 3 mm. Only one unblended and one partially blended line were identified, many more were severely bleded or too weak. The derived CH<sub>3</sub><sup>18</sup>OH to CH<sub>3</sub><sup>17</sup>OH ratio of ~3.3 is along <sup>18</sup>O to <sup>17</sup>O ratios found for other molecules in the Galactic Center as is the CH<sub>3</sub><sup>16</sup>OH to CH<sub>3</sub><sup>18</sup>OH ratio of 240.\\
Line 78:		Line 78:
	Y. Watanabe, T. Oyama, A. Tamanai, S. Zeng, and N. Sakai\\		Y. Watanabe, T. Oyama, A. Tamanai, S. Zeng, and N. Sakai\\
	reported on\\		reported on\\
-	[[https://doi.org/10.1051/0004-6361/202556325\|Investigation of the Rotational Spectrum of CH<sub>3</sub><sup>17</sup>OH and its Tentative Detection toward Sagittarius B2(N)]]\\	+	[[https://doi.org/10.1051/0004-6361/202556325\|Observation of CH3(17)OH and CH3(18)OH in Orion KL: A new Tool to Study Star Formation History]]\\
	//Astron. Astrophys.// 705, Art. No. A132 (2026).\\		//Astron. Astrophys.// 705, Art. No. A132 (2026).\\
		+	The authors analyzed archival ALMA data near 231.89 GHz and 236.5 GHz and derived a CH<sub>3</sub><sup>18</sup>OH to CH<sub>3</sub><sup>17</sup>OH ratio of ~3.4–3.5, which corresponds to the expected <sup>18</sup>O/<sup>17</sup>O ratio at this galactocentric distance, reiteration the potential of methanol as a proble into the <sup>18</sup>O/<sup>17</sup>O ratio, as already done by Müller et al. in the previous paragraph.\\
		+	\\
	\\		\\

cn-minus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:11:06 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of the Cyanide Ion, CN–, in Space =====
	+
	+	The cyanide ion has been detected with the IRAM 30 m telescope in the circumstellar shell of the carbon rich star CW Leo (IRC +10216) in 3 rotational transitions from //J// = 1 – 0 to 3 – 2 which occur between 110 and 340 GHz:\\
	+	M. Agúndez, J. Cernicharo, M. Guélin, C. Kahane, E. Roueff, J. Klos, F. J. Aoiz, F. Lique, N. Marceliño, J. R. Goicoechea, M. González García, C. A. Gottlieb, M. C. McCarthy, and P. Thaddeus,\\
	+	[[https://doi.org/10.1051/0004-6361/201015186\|Astronomical Identification of CN<sup>–</sup>, the Smallest Observed Molecular Anion]]\\
	+	//Astron. Astrophys.// 517, Art. No. L2 (2010).\\
	+	It should be mentioned that the 1 – 0 transition is heavily blended with a line of C<sub>6</sub>H, however a weak shoulder seems to be due to the anion. The 2 – 1 transitions is partially blended, partially it appears to be clear. The 3 – 2 transition seems to be unblended. The number of transitions is somewhat low, nevertheless, the detection appears to be safe, in particular when one takes into consideration the line shapes, abundance, and rotational temperature.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 7, 2010
	+
	+
	+	----
	+

cncn

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:11:03 +0000

2019/02/25 22:38		current
Line 4:		Line 4:
	M. Agúndez, N. Marcelino, and J. Cernicharo,\\		M. Agúndez, N. Marcelino, and J. Cernicharo,\\
	reported on the\\		reported on the\\
-	[[http://dx.doi.org/10.1051/0004-6361/201526317\|Discovery of Interstellar Isocyanogen (CNCN): Further Evidence that Dicyanopolyynes Are Abundant in Space]]\\	+	[[https://doi.org/10.3847/2041-8213/aad089\|Discovery of Interstellar Isocyanogen (CNCN): Further Evidence that Dicyanopolyynes Are Abundant in Space]]\\
	//Astrophys. J.// 861, Art. No. L22 (2018).\\		//Astrophys. J.// 861, Art. No. L22 (2018).\\
	The IRAM 30 m telescope was used to detect three transitions out of four transitions with //J// = 8 – 7 near 82.8 GHz to //J// = 11 – 10 near 113.8 GHz toward the the young stellar object IRAS 18148–0440 in the L483 dense core. The signal-to-noise (S/N) ratios were reasonable to good for the first three transitions, not sufficient for the last. All four transitions were also seen with modest S/N toward the cyanopolyyne peak of TMC-1; stacking of all four transitions yielded a reasonable signal. Hence, the detection was viewed as secure toward L483 and as tentative toward TMC-1. CNCN is more abundant than HNCCN<sup>+</sup> by factors of about 40 and 10 in L483 and TMC-1, respectively.		The IRAM 30 m telescope was used to detect three transitions out of four transitions with //J// = 8 – 7 near 82.8 GHz to //J// = 11 – 10 near 113.8 GHz toward the the young stellar object IRAS 18148–0440 in the L483 dense core. The signal-to-noise (S/N) ratios were reasonable to good for the first three transitions, not sufficient for the last. All four transitions were also seen with modest S/N toward the cyanopolyyne peak of TMC-1; stacking of all four transitions yielded a reasonable signal. Hence, the detection was viewed as secure toward L483 and as tentative toward TMC-1. CNCN is more abundant than HNCCN<sup>+</sup> by factors of about 40 and 10 in L483 and TMC-1, respectively.
Line 12:		Line 12:

	Contributor(s): H. S. P. Müller; 07, 2018		Contributor(s): H. S. P. Müller; 07, 2018
-

	----		----

co-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:48:34 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Observations of CO+ =====
	+
	+	CO<sup>+</sup> is a typical PDR molecule particularly intense in the molecular cloud/HII interface region. The two strongest fine structure lines of the //N// = 2 – 1 transition as well as one fs component of the 3 – 2 transition were detected in the vicinity of the M17SW cloud by\\
	+	W. B. Latter, C. K. Walker, and P. R. Maloney,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1993ApJ...419L..97L\|Detection of the Carbon Monoxide Ion (CO<sup>+</sup>) in the Interstellar Medium and a Planetary Nebula]]\\
	+	//Astrophys. J.// 419, L97–L100 (1993).\\
	+	The strongest 2 – 1 line was also detected toward the planetary nebula NGC 7027; this is a late type star phase after the AGB (asymptotic giant branch) phase.
	+
	+	The molecular cation has also been seen in the reflection nebula NGC 7023 which is in the vicinity of a Be star:\\
	+	A. Fuente, J. Martin-Pintado,\\
	+	[[https://doi.org/10.1086/310532\|Detection of CO<sup>+</sup> toward the Reflection Nebula NGC 7023]]\\
	+	//Astrophys. J.// 477, L107–L109 (1997).
	+
	+	C. Ceccarelli, E. Caux, M.Wolfire, A. Rudolph, B. Nisini, P. Saraceno, and G.J. White,\\
	+	have reported on\\
	+	[[https://ui.adsabs.harvard.edu/abs/1998A%26A...331L..17C\|ISO Detection of CO<sup>+</sup> toward the protostar IRAS 16293–2422]]\\
	+	//Astron. Astrophys.// 331, L17–L20 (1998)\\
	+	in rather highly excited rotational states (//N// = 14 – 13 to 21 – 20). The authors attributed this to J-shocks.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2009
	+
	+
	+	----
	+

cp

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:49:10 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of the Phosphaethynyl Radical, CP, toward IRC +10216 =====
	+
	+	The phosphaethynyl radical, CP, has been detected in five lines of three rotational transitions in the millimeter-wave region:\\
	+	M. Guélin, J. Cernicharo, G.Paubert, and B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1990A%26A...230L...9G\|Free CP in IRC +10216]]\\
	+	//Astron. Astrophys.// 230, L9–L11 (1990).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2007
	+
	+
	+	----
	+

cyanamid

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:13:27 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on Cyanamide, H2NCN, in the ISM =====
	+
	+	Cyanamide seems to be a fairly typical hot core molecule that is quite abundant. The 4<sub>1,3</sub> – 3<sub>1,2</sub> and 5<sub>1,4</sub> – 4<sub>1,3</sub> transitions of this molecule near 80.5 and 100.6 GHz were detected with the NRAO 11 m telescope toward Sgr B2 by\\
	+	B. E. Turner, H. S. Liszt, N. Kaifu, and A. G. Kisliakov,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1975ApJ...201L.149T\|Microwave Detection of Interstellar Cyanamide]]\\
	+	//Astrophys. J.// 201, L149–L152 (1975).\\
	+	Additional transitions were detected later. Furthermore, the molecule has also been detected in other hot core sources.
	+
	+	A. Coutens, E. R. Willis, R. T. Garrod, H. S. P. Müller, T. L. Bourke, H. Calcutt, M. N. Drozdovskaya, J. K. Jørgensen, N. F. W. Ligterink, M. V. Persson, G. Stéphan, M. H. D. van der Wiel, E. F. van Dishoeck, and S. F. Wampfler\\
	+	reported the\\
	+	[[https://doi.org/10.1051/0004-6361/201732346\|First Detection of Cyanamide (NH<sub>2</sub>CN) towards Solar-type Protostars]]\\
	+	//Astron. Astrophys.// 612, Art. No. A107 (2018).\\
	+	The Protostellar Interferometric Line Survey (PILS) of IRAS 16293–2422 with ALMA was used to identify 11 transitions of both tunneling components of cyanamide toward source B. A quantitative analysis was complicated by the interplay between absorption from the less dense envelope and emission from the hot corino associated with the secondary protostar. The situation is more favorable for the NH<sub>2</sub><sup>13</sup>CN and NHDCN isotopologs for which 3 and 9 lines, respectively, were detected. The column density of NH<sub>2</sub>CN in the hot corino was derived assuming a <sup>12</sup>C/<sup>13</sup>C ratio of 68, typical for the local ISM. This yielded a D/H ratio per H atom of about 1.7 %, similar to what was observed for formamide from the same survey. Please note that a lower <sup>12</sup>C/<sup>13</sup>C ratio would yield an equivalently higher D/H ratio.\\
	+	\\
	+	The authors also detected NH<sub>2</sub>CN toward NGC 1333 IRAS2A with PdBI. Three lines come from their own observations, and five more apparently unblended lines from a study in which these lines remained unidentified. Cyanamide appears to be usually less abundant than formamide by factors of a few, but may be similarly abundant in Orion KL.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2011; 05, 2018
	+
	+	----
	+

cyanoacenaphtalin

anonymous@undisclosed.example.com (Anonymous) — Thu, 22 Jan 2026 13:04:40 +0000

2026/01/09 13:06		current
Line 15:		Line 15:
	J. Cernicharo, B. Tercero, N. Marcelino, J. A. López-Pérez, J. D. Gallego, F. Tercero, G. Esplugues, C. Cabezas, M. Agúndez, C. Limeres, A. L. Steber, D. Pérez, C. Pérez, A. Lesarri, and P. de Vicente\\		J. Cernicharo, B. Tercero, N. Marcelino, J. A. López-Pérez, J. D. Gallego, F. Tercero, G. Esplugues, C. Cabezas, M. Agúndez, C. Limeres, A. L. Steber, D. Pérez, C. Pérez, A. Lesarri, and P. de Vicente\\
	announced the\\		announced the\\
-	[[https://doi.org/10.1051/0004-6361/202452196\|Discovery of Two New Isomers of Cyanoacenaphthylene (C<sub>12</sub>H<sub>8</sub>) in the Taurus molecular cloud 1 with the QUIJOTE Line Survey]]\\	+	[[https://doi.org/10.1051/0004-6361/202557893\|Discovery of Two New Isomers of Cyanoacenaphthylene (C<sub>12</sub>H<sub>8</sub>) in the Taurus molecular cloud 1 with the QUIJOTE Line Survey]]\\
	//Astron. Astrophys.// 705, Art. No. L7 (2026).\\		//Astron. Astrophys.// 705, Art. No. L7 (2026).\\
-	The identifications were made under conditions similar to the previous two isomers.\\	+	The identifications were made under conditions similar to the previous two isomers. The column densities of 3- and 4-cyanoacenaphthylene are about 3/4 and 1/2, respectively of those of each of the 1- and 5 cyanoacenaphthylene isomers.\\
	\\		\\

cyanoallen

anonymous@undisclosed.example.com (Anonymous) — Fri, 26 Apr 2019 13:36:13 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== 2,3-Butadienenitrile, CH2CCHCN, in Space =====
	+
	+	2,3-Butadienenitrile, CH<sub>2</sub>CCHCN, aka cyanoallene, has been detected with the 100m Greenbank telescope toward TMC-1:\\
	+	F. J. Lovas, A. J. Remijan, J. M. Hollis, P. R. Jewell, and L. E. Snyder,\\
	+	[[https://doi.org/10.1086/500431\|Hyperfine Structure Identification of Interstellar Cyanoallene toward TMC-1]]\\
	+	//Astrophys. J.// 637, L37–L40 (2006).\\
	+	As the number of four observed rotational transitions is somewhat small, the (partial) resolution of the <sup>14</sup>N hyperfine structure is a decisive aspect in securing the detection.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 02, 2006
	+
	+
	+	----
	+

cyanocoronen

anonymous@undisclosed.example.com (Anonymous) — Thu, 15 May 2025 12:03:01 +0000

2025/05/15 13:50		current
Line 3:		Line 3:
	G. Wenzel, S. Gong, C. Xue, P. B. Changala, M. S. Holdren, T. H. Speak, D. A. Stewart, Z. T. P. Fried, R. H. J. Willis, E. A. Bergin, A. M. Burkhardt, A. N. Byrne, S. B. Charnley, A. Lipnicky, R. A. Loomis, C. N. Shingledecker, I. R. Cooke, M. C. McCarthy, A. J. Remijan, A. E. Wendlandt, and B. A. McGuire\\		G. Wenzel, S. Gong, C. Xue, P. B. Changala, M. S. Holdren, T. H. Speak, D. A. Stewart, Z. T. P. Fried, R. H. J. Willis, E. A. Bergin, A. M. Burkhardt, A. N. Byrne, S. B. Charnley, A. Lipnicky, R. A. Loomis, C. N. Shingledecker, I. R. Cooke, M. C. McCarthy, A. J. Remijan, A. E. Wendlandt, and B. A. McGuire\\
	a<nnounced the\\		a<nnounced the\\
-	[[https://doi.org/10.3847/2041-8213/adc911\|Discovery of the Seven-ring Polycyclic Aromatic Hydrocarbon Cyanocoronene (C24H11CN) in GOTHAM Observations of TMC-1]]\\	+	[[https://doi.org/10.3847/2041-8213/adc911\|Discovery of the Seven-ring Polycyclic Aromatic Hydrocarbon Cyanocoronene (C<sub>24</sub>H<sub>11</sub>CN) in GOTHAM Observations of TMC-1]]\\
	//Astrophys. J. Lett.// 984, Art. No. L36 (2025).\\		//Astrophys. J. Lett.// 984, Art. No. L36 (2025).\\
-	The molecule was identified in the course of the GOTHAM survey of TMC-1 carried out with the 100 m GBT dish. Several oblate paired //a//-type rotational transitions with 31 ≤ //J// ≤ 37 and //K<sub>c</sub>// close to //J//. Each pair of lines is close to the noise limit, but stacking achieves a S/N of about 7. The derived column density is, for example, about twice that of each of 1- and 2-cyanonaphtalene and only slightly less than that of benzonitrile.\\	+	The molecule was identified in the course of the GOTHAM survey of TMC-1 carried out with the 100 m GBT dish. Several oblate paired //a//-type rotational transitions were observed. Several of these had an S/N of about 3; stacking improved the result. The derived column density is comparable to many related aromatic cyano derivatives, highest among individual presently known ones. A rotational temperature of 6 K was derived with great accuracy.\\
	\\		\\

cyanocyclopentadien

anonymous@undisclosed.example.com (Anonymous) — Tue, 13 Apr 2021 09:32:39 +0000

2021/04/12 18:01		current
Line 11:		Line 11:
	[[https://doi.org/10.3847/2041-8213/abe764\|Interstellar Detection of 2-cyanocyclopentadiene, C<sub>5</sub>H<sub>5</sub>CN, a Second Five-membered Ring toward TMC-1]]\\		[[https://doi.org/10.3847/2041-8213/abe764\|Interstellar Detection of 2-cyanocyclopentadiene, C<sub>5</sub>H<sub>5</sub>CN, a Second Five-membered Ring toward TMC-1]]\\
	//Astrophys. J. Lett.// 910, L2 (2021).\\		//Astrophys. J. Lett.// 910, L2 (2021).\\
		+	Same procedure, albeit new observations increased the signal-to-noise ratios of both molecules. Some smoothing reavealed individual lines for 1-cyanocyclopentadiene, which has stronger lines. Four lines were shown.\\

cyanoinden

anonymous@undisclosed.example.com (Anonymous) — Fri, 21 Oct 2022 12:04:28 +0000

2022/10/21 14:03		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/ac92f4\|Discovery of Interstellar 2-Cyanoindene (2-C<sub>9</sub>H<sub>9</sub>CN) in GOTHAM Observations of TMC-1]]\\		[[https://doi.org/10.3847/2041-8213/ac92f4\|Discovery of Interstellar 2-Cyanoindene (2-C<sub>9</sub>H<sub>9</sub>CN) in GOTHAM Observations of TMC-1]]\\
	//Astrophys. J. Lett.// 938, Art. No. L12 (2022).\\		//Astrophys. J. Lett.// 938, Art. No. L12 (2022).\\
-	The lowest energy isomer of the cyanoindenes was detected through the usually stacking technique employing TMC-1 observations with the GBT between 6 and 40 GHz in the frtamework of the GOTHAM survey. Four other isomers were not detected, for two additional ones no laboratory data exist at present. The molecules is about a factor of 43 less abundant than the parent indene molecule. 1- and 2-cyanopentadiene are approximately factors of 14.5 and 63 less abundant than the parent molecule pentadiene.\\	+	The lowest energy isomer of the cyanoindenes was detected through the usual stacking technique employing observations of TMC-1 with the GBT between 6 and 40 GHz in the framework of the GOTHAM survey. Four other isomers were not detected, for two additional ones no laboratory data exist at present. The molecules is about a factor of 43 less abundant than the parent indene molecule. 1- and 2-cyanopentadiene are approximately factors of 14.5 and 63 less abundant than the parent molecule pentadiene.\\
	\\		\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 10, 2022
		+
		+	----

cyanomethanimin

anonymous@undisclosed.example.com (Anonymous) — Fri, 17 May 2024 14:08:24 +0000

2024/05/17 16:06		current
Line 20:		Line 20:
	[[https://doi.org/10.1093/mnrasl/sly228\|Abundant Z-cyanomethanimine in the Interstellar Medium: Paving the Way to the Synthesis of Adenine]]\\		[[https://doi.org/10.1093/mnrasl/sly228\|Abundant Z-cyanomethanimine in the Interstellar Medium: Paving the Way to the Synthesis of Adenine]]\\
	//Mon. Not. R. Soc. Astron.// 483, L114–L119 (2019).\\		//Mon. Not. R. Soc. Astron.// 483, L114–L119 (2019).\\
-	The results were obtained in the course of a line survey of the Galactic center source G 0.693–0.03 at 3 mm using the IRAM 30 m dish; additional observation around 1.3 cm were carried out with the GBT 100 m dish. The E-conformer was also identified. The Z/E ratio of about six indicated thermal equilibrium at the kinetic temperature of the cloud. The excitation temperature, in contrast, is rather cold, about 8 K.\\	+	The results were obtained in the course of a line survey of the Galactic center source G 0.693–0.03 at 3 mm using the IRAM 30 m dish; additional observation around 1.3 cm were carried out with the GBT 100 m dish. The //E//-conformer was also identified. The Z/E ratio of about six indicated thermal equilibrium at the kinetic temperature of the cloud. The excitation temperature, in contrast, is rather cold, about 8 K.\\
	\\		\\

Line 27:		Line 27:
	[[https://doi.org/10.3847/1538-4357/ad3af3\|First Detection in Space of the High-energy Isomer of Cyanomethanimine: H<sub>2</sub>CNCN]]\\		[[https://doi.org/10.3847/1538-4357/ad3af3\|First Detection in Space of the High-energy Isomer of Cyanomethanimine: H<sub>2</sub>CNCN]]\\
	//Astrophys. J.// 967, Art. No 39 (2024).\\		//Astrophys. J.// 967, Art. No 39 (2024).\\
-	The results were obtained in the course of line surveys of the Galactic center source G 0.693–0.03 using the Yebes 40 m and IRAM 30 m telescopes. 14 //a//-type transitions with 2 ≤ //J// ≤ 10, //K<sub>a</sub>// ≤ 2 were identified between 31 and 107 GHz. Six of these transitions were unblended or only slightly blended. A non-thermal C-/N-cyanomethanimine ratio of ~32 was derived, while the //Z//-///E//-cyanomethanimine ratio of ~4.5 was deemed to be thermal, as may be expected for a pair of conformers. In contrast, N-cyanomethanimine is an isomer ov C-cyanomethanimine, meaning, it requires the formal breaking of at least one bond for interconversion.\\	+	The results were obtained in the course of line surveys of the Galactic center source G 0.693–0.03 using the Yebes 40 m and IRAM 30 m telescopes. 14 //a//-type transitions with 2 ≤ //J// ≤ 10, //K<sub>a</sub>// ≤ 2 were identified between 31 and 107 GHz. Six of these transitions were unblended or only slightly blended. A non-thermal C-/N-cyanomethanimine ratio of ~32 was derived, while the //Z//-///E//-cyanomethanimine ratio of ~4.5 was deemed to be thermal, as may be expected for a pair of conformers. In contrast, N-cyanomethanimine is an isomer of C-cyanomethanimine, meaning, it requires the formal breaking of at least one bond for interconversion.\\
	\\		\\

cyanonaphtalin

anonymous@undisclosed.example.com (Anonymous) — Mon, 28 Oct 2024 09:10:18 +0000

2021/04/13 12:16		current
Line 1:		Line 1:
-	===== On the Detection of Cyanonaphtalenes, C11H7CN, in the ISM =====	+	===== On the Detection of Cyanonaphtalenes, C<sub>10</sub>H<sub>7</sub>CN, in the ISM =====

	B. A. McGuire, R. A. Loomis, A. M. Burkhardt, K. L. K. Lee, C. N. Shingledecker, S. B. Charnley, I. R. Cooke, M. A. Cordiner, E. Herbst, S. Kalenskii, M. A. Siebert, E. R. Willis, C. Xue, A. J. Remijan, M. C. McCarthy\\		B. A. McGuire, R. A. Loomis, A. M. Burkhardt, K. L. K. Lee, C. N. Shingledecker, S. B. Charnley, I. R. Cooke, M. A. Cordiner, E. Herbst, S. Kalenskii, M. A. Siebert, E. R. Willis, C. Xue, A. J. Remijan, M. C. McCarthy\\
Line 6:		Line 6:
	//Science// 371, 1265−1269 (2021).\\		//Science// 371, 1265−1269 (2021).\\
	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. The molecules 1-cyanonaphtalene and 2-cyanonaphtalene were indentified through line-stacking with good signal-to-noise ratios. In fact, after additional observations carried out in the review process, the S/Ns of some lines of 1-cyanonaphtalene were good enough to be identified individually after modest smoothing. Both molecules are obviously not hydrocarbons, but simple hydrocarbon derivatives.\\		The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. The molecules 1-cyanonaphtalene and 2-cyanonaphtalene were indentified through line-stacking with good signal-to-noise ratios. In fact, after additional observations carried out in the review process, the S/Ns of some lines of 1-cyanonaphtalene were good enough to be identified individually after modest smoothing. Both molecules are obviously not hydrocarbons, but simple hydrocarbon derivatives.\\
		+	\\

	----		----

cyanopropargyl

anonymous@undisclosed.example.com (Anonymous) — Thu, 30 Jan 2025 14:26:28 +0000

2025/01/17 14:36		current
Line 1:		Line 1:
	===== On the Detection of Cyanopropargyl in the ISM =====		===== On the Detection of Cyanopropargyl in the ISM =====

-	C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, J. R. Pardo, P. de Vicente, and J. Cernicharo \\	+	C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, J. R. Pardo, P. de Vicente, and J. Cernicharo\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.1051/0004-6361/202142156\|Discovery of Interstellar 3-Cyanopropargyl Radical, CH<sub>2</sub>CCCN]]\\		[[https://doi.org/10.1051/0004-6361/202142156\|Discovery of Interstellar 3-Cyanopropargyl Radical, CH<sub>2</sub>CCCN]]\\
Line 13:		Line 13:
	[[https://doi.org/10.1051/0004-6361/202453419\|Identification of the Interstellar 1-Cyanopropargyl Radical (HCCCHCN) in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202453419\|Identification of the Interstellar 1-Cyanopropargyl Radical (HCCCHCN) in TMC-1]]\\
	//Astron. Astrophys.// 693, Art. No. L14 (2025).\\		//Astron. Astrophys.// 693, Art. No. L14 (2025).\\
		+	Eight //a//-type transitions with 5 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 1 were covered with complex fine and hyperfine structure splitting. Many features are close to the noise limit or blended, but sufficiently many features are clear enough and modeled well enough to view the detection as secure. A value of //T//<sub>rot</sub> = 7 ± 1 K was derived for this isomer as well. The abundance of 1-cyanopropargyl is slightly higher than that of 3-cyanopropargyl by a factor of about 1.4.\\
		+	\\


	----		----

-	Contributor(s): H. S. P. Müller; 11, 2021	+	Contributor(s): H. S. P. Müller; 11, 2021; 01, 2025

	----		----

cyanopyren

anonymous@undisclosed.example.com (Anonymous) — Thu, 15 May 2025 11:51:08 +0000

2025/02/24 16:10		current
Line 5:		Line 5:
	[[https://doi.org/10.1126/science.adq6391\|Detection of Interstellar 1-Cyanopyrene: A Four-ring Polycyclic Aromatic Hydrocarbon]]\\		[[https://doi.org/10.1126/science.adq6391\|Detection of Interstellar 1-Cyanopyrene: A Four-ring Polycyclic Aromatic Hydrocarbon]]\\
	//Science// 386, 810−813 (2024).\\		//Science// 386, 810−813 (2024).\\
-	The molecule was identified in the course of the GOTHAM survey of TMC-1 casrried out with the 100 m GBT dish. Several oblate paired //a//-type rotational transitions with 31 ≤ //J// ≤ 37 and //K<sub>c</sub>// close to //J//. Each pair of lines is close to the noise limit, but stacking achieves a S/N of about 7. The derived column density is, for example, about twice that of each of 1- and 2-cyanonaphtalene and only slightly less than that of benzonitrile.\\	+	The molecule was identified in the course of the GOTHAM survey of TMC-1 carried out with the 100 m GBT dish. Several oblate paired //a//-type rotational transitions with 31 ≤ //J// ≤ 37 and //K<sub>c</sub>// close to //J//. Each pair of lines is close to the noise limit, but stacking achieves a S/N of about 7. The derived column density is, for example, about twice that of each of 1- and 2-cyanonaphtalene and only slightly less than that of benzonitrile.\\
	The CfA issued a [[https://www.cfa.harvard.edu/news/astronomers-discover-new-building-blocks-complex-organic-matter\|press release]].\\		The CfA issued a [[https://www.cfa.harvard.edu/news/astronomers-discover-new-building-blocks-complex-organic-matter\|press release]].\\
	\\		\\
Line 11:		Line 11:
	G. Wenzel, T. H. Speak, P. B. Changala, R. H. J. Willis, A. M. Burkhardt, S. Zhang, E. A. Bergin, A. N. Byrne, S. B. Charnley, Z. T. P. Fried, H. Gupta, E. Herbst, M. S. Holdren, A. Lipnicky, R. A. Loomis, C. N. Shingledecker, C. Xue, A. J. Remijan, A. E. Wendlandt, M. C. McCarthy, I. R. Cooke, and B. A. McGuire\\		G. Wenzel, T. H. Speak, P. B. Changala, R. H. J. Willis, A. M. Burkhardt, S. Zhang, E. A. Bergin, A. N. Byrne, S. B. Charnley, Z. T. P. Fried, H. Gupta, E. Herbst, M. S. Holdren, A. Lipnicky, R. A. Loomis, C. N. Shingledecker, C. Xue, A. J. Remijan, A. E. Wendlandt, M. C. McCarthy, I. R. Cooke, and B. A. McGuire\\
	announced the\\		announced the\\
-	[[https://doi.org/10.1126/science.adq6391\|Detections of Interstellar Aromatic Nitriles 2-Cyanopyrene and 4-Cyanopyrene in TMC-1]]\\	+	[[https://doi.org/10.1038/s41550-024-02410-9\|Detections of Interstellar Aromatic Nitriles 2-Cyanopyrene and 4-Cyanopyrene in TMC-1]]\\
	//Nat. Atron.// 9, 262−270 (2025).\\		//Nat. Atron.// 9, 262−270 (2025).\\
	The isomers of 1-cyanopyrene were detected in a manner very similar to this one. The derived column densities of 1-cyanopyrene : 2-cyanopyrene : 4-cyanopyrene are compatible with the 4 : 2 : 4 ratios of the number of equivalent substitution positions in pyrene.\\		The isomers of 1-cyanopyrene were detected in a manner very similar to this one. The derived column densities of 1-cyanopyrene : 2-cyanopyrene : 4-cyanopyrene are compatible with the 4 : 2 : 4 ratios of the number of equivalent substitution positions in pyrene.\\

cyclopentadien

anonymous@undisclosed.example.com (Anonymous) — Tue, 18 May 2021 13:25:51 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Cyclopentadiene in the ISM =====
	+
	+	J. Cernicharo, M. Agúndez, C. Cabezas, B. Tercero, N. Marcelino, J. R. Pardo, and P. de Vicente\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/202141156\|Pure hydrocarbon cycles in TMC-1: Discovery of ethynylcyclopropenylidene, cyclopentadiene, and indene]]\\
	+	//Astron. Astrophys.// 649, Art. No. L15 (2021).\\
	+	Cyclopentadiene, //c//-C<sub>5</sub>H<sub>6</sub>, was identified through five unblended or slightly blended //b//-type lines with 2 ≤ //J// ≤ 5 and //K<sub>a</sub>// ≤ 3 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. One line corresponds to the unresolved //K<sub>c</sub>// = //J// = 5 − 4 asymmetry doublet. A value of //T//<sub>rot</sub> = 10 K was assumed. The column density of //c//-C<sub>5</sub>H<sub>6</sub> is about the same as the C<sub>4</sub>H<sub>4</sub> isomers butenyne and ethynylallene. It is about a factor of 7 lower than that of C<sub>3</sub>H<sub>3</sub> and about factors of 15 and 63 higher than the 1- and 2-cyano derivatives of //c//-C<sub>5</sub>H<sub>6</sub>.\\
	+
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2021
	+
	+	----

cyclopropenon

anonymous@undisclosed.example.com (Anonymous) — Tue, 03 Feb 2026 13:29:36 +0000

2026/02/03 13:21		current
Line 16:		Line 16:

	In their work on the\\		In their work on the\\
-	[[https://doi.org/10.1051/0004-6361/202557355\|Discovery of Linear Propadienone — Study of the Cof linear and Cyclic H2C3O and H2C3S in TMC-1]]\\	+	[[https://doi.org/10.1051/0004-6361/202557355\|Discovery of Linear Propadienone — Study of the Chemistry of Linear and Cyclic H2C3O and H2C3S in TMC-1]]\\
	//Astron. Astrophys.// 705, Art. No. A206 (2026),\\		//Astron. Astrophys.// 705, Art. No. A206 (2026),\\
	G. Esplugues, J. C. Loison, M. Agúndez, G. Molpeceres, N. Marcelino, B. Tercero, and J. Cernicharo\\		G. Esplugues, J. C. Loison, M. Agúndez, G. Molpeceres, N. Marcelino, B. Tercero, and J. Cernicharo\\
-	also identify isotopic species of cyclopropenone. Two //a//-type transitions were detected for the C<sub>2</sub> (ethene-type) position, c-H<sub>2</sub><sup>13</sup>CCCO, yielding a c-H<sub>2</sub>C<sub>3</sub>O to c-H<sub>2</sub><sup>13</sup>CCCO of 23 ± 9 and a <sup>12</sup>C to <sup>13</sup>C ratio of 46 ± 18 because of the two equivalent C<sub>2</sub> positions. Only one //a//-type transition had enough intensity in the case of the carbonyl C (C<sub>1</sub>), making the identification somewhat tentative. The <sup>12</sup>C to <sup>13</sup>C ratio is about 57.	+	also identify isotopic species of cyclopropenone. Two //a//-type transitions were detected for the C<sub>2</sub> (ethene-type) position, c-H<sub>2</sub><sup>13</sup>CCCO, yielding a c-H<sub>2</sub>C<sub>3</sub>O to c-H<sub>2</sub><sup>13</sup>CCCO of 23 ± 9 and a <sup>12</sup>C to <sup>13</sup>C ratio of 46 ± 18 because of the two equivalent C<sub>2</sub> positions. Only one //a//-type transition had enough intensity in the case of the carbonyl C (C<sub>1</sub>), making the identification somewhat tentative. The <sup>12</sup>C to <sup>13</sup>C ratio is about 57. c-HDC<sub>3</sub>O was also identified with a H to D ratio of 24 ± 10 because of the two equivalent H positions.\\
		+	\\

cyclopropenonthion

anonymous@undisclosed.example.com (Anonymous) — Tue, 03 Feb 2026 14:06:20 +0000

2026/02/03 15:02		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/1538-4357/adb84c\|The Missing Link of Sulfur Chemistry in TMC-1: The Detection of //c//-C<sub>3</sub>H<sub>2</sub>S from the GOTHAM Survey]]\\		[[https://doi.org/10.3847/1538-4357/adb84c\|The Missing Link of Sulfur Chemistry in TMC-1: The Detection of //c//-C<sub>3</sub>H<sub>2</sub>S from the GOTHAM Survey]]\\
	//Astrophys. J.// 982, Art. No. 191 (2025).\\		//Astrophys. J.// 982, Art. No. 191 (2025).\\
-	The molecule was identified through line-stacking in the course of the GOTHAM survey of TMC-1 carried out with the 100 m GBT dish and covering a large fraction of the 3.9 to 36.4 GHz region. An excitation temperature of ~5 K was derived. The abundance ratio of CH<sub>2</sub>CCS///c//-C<sub>3</sub>H<sub>2</sub>S is about 10 while that of HCCCHS///c//-C<sub>3</sub>H<sub>2</sub>S is about 5.6.\\	+	The molecule was identified through line-stacking in the course of the GOTHAM survey of TMC-1 carried out with the 100 m GBT dish and covering a large fraction of the 3.9 to 36.4 GHz region. An excitation temperature of ~5 K was derived. The abundance ratio of CH<sub>2</sub>CCS / //c//-C<sub>3</sub>H<sub>2</sub>S is about 10 while that of HCCCHS / //c//-C<sub>3</sub>H<sub>2</sub>S is about 5.6.\\
		+	\\
		+
		+	In their work on the\\
		+	[[https://doi.org/10.1051/0004-6361/202557355\|Discovery of Linear Propadienone — Study of the Chemistry of Linear and Cyclic H2C3O and H2C3S in TMC-1]]\\
		+	//Astron. Astrophys.// 705, Art. No. A206 (2026),\\
		+	G. Esplugues, J. C. Loison, M. Agúndez, G. Molpeceres, N. Marcelino, B. Tercero, and J. Cernicharo\\
		+	also identify cyclopropenethione in a line by line way. Their CH<sub>2</sub>CCS to HCCCHS to //c//-C<sub>3</sub>H<sub>2</sub>S ratios are about 15.4 to 6.7 to 1, in fairly good agreement with ratios obtained above.\\
	\\		\\

	----		----

-	Contributor(s): H. S. P. Müller; 04, 2025	+	Contributor(s): H. S. P. Müller; 04, 2025; 02, 2026

	----		----

dicyanide

anonymous@undisclosed.example.com (Anonymous) — Tue, 03 Sep 2024 14:13:40 +0000

2024/09/03 16:11		current
Line 6:		Line 6:
	//Astron. Astrophys.// 688, Art. No. L31 (2024).\\		//Astron. Astrophys.// 688, Art. No. L31 (2024).\\
	Both molecules were detected in the course of the QUIJOTE line survey of the dark cloud TMC-1 with the Yebes 40 m dish.		Both molecules were detected in the course of the QUIJOTE line survey of the dark cloud TMC-1 with the Yebes 40 m dish.
-	Dicyanomethane or malononitrile was identified through four rotational transitions with modest S/N and partially resolved <sup>14</sup>N HFS splitting and 4 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 1. Other lines are heavily blended or have a lower S/N. //Z//-1,2-Dicyanoethene or maleonitrile was identified through four rotational transitions with modest S/N of which one displayed partially resolved <sup>14</sup>N HFS splitting; one HFS line of another transition is shown as are some blended lines. The abundance ratio of dicyanomethane to //Z//-1,2-dicyanoethene is about 3.5. Related molecules with one CN replaced by CCH are more abundant by varying degrees, consisten with a CCH to CN ration in TMC-1 of about 10.\\	+	Dicyanomethane or malononitrile was identified through four rotational transitions with modest S/N and partially resolved <sup>14</sup>N HFS splitting and 4 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 1. Other lines are heavily blended or have a lower S/N. //Z//-1,2-Dicyanoethene or maleonitrile was identified through four rotational transitions with modest S/N of which one displayed partially resolved <sup>14</sup>N HFS splitting; one HFS line of another transition is shown as are some blended lines. The quantum numbers were 7 ≤ //J// ≤ 11 and //K<sub>a</sub>// ≤ 1. The abundance ratio of dicyanomethane to //Z//-1,2-dicyanoethene is about 3.5. Related molecules with one CN replaced by CCH are more abundant by varying degrees, consistent with a CCH to CN ration in TMC-1 of about 10.\\
	\\		\\

dme

anonymous@undisclosed.example.com (Anonymous) — Tue, 24 Aug 2021 11:37:43 +0000

2021/08/24 13:33		current
Line 1:		Line 1:
-	===== On the Detection of Dimethyl Ether, (CH3)2O, in the ISM =====	+	===== On the Detection of Dimethyl Ether, (CH<sub>3</sub>)<sub>2</sub>O, in the ISM =====

	L. E. Snyder, D. Buhl, P. R. Schwartz, F. O. Clark, D. R. Johnson, F. J. Lovas, and P. T. Giguere,\\		L. E. Snyder, D. Buhl, P. R. Schwartz, F. O. Clark, D. R. Johnson, F. J. Lovas, and P. T. Giguere,\\
Line 41:		Line 41:
	[[https://doi.org/10.1051/0004-6361/202141282\|Laboratory Rotational Spectra of Doubly Deuterated Dimethyl Ether (CH<sub>3</sub>OCHD<sub>2</sub>) — First ALMA Detection in the Interstellar Medium]]\\		[[https://doi.org/10.1051/0004-6361/202141282\|Laboratory Rotational Spectra of Doubly Deuterated Dimethyl Ether (CH<sub>3</sub>OCHD<sub>2</sub>) — First ALMA Detection in the Interstellar Medium]]\\
	//Astron. Astrophys.// 651, Art. No. A120 (2021).\\		//Astron. Astrophys.// 651, Art. No. A120 (2021).\\
-	The isotopolog was detected through numerous transitions in the course of the Protostellar Interferometric Line Survey (PILS) of IRAS 16293−2422 with ALMA between 329.1 and 362.9 GHz.	+	The isotopolog was detected through numerous transitions in the course of the Protostellar Interferometric Line Survey (PILS) of IRAS 16293−2422 with ALMA between 329.1 and 362.9 GHz. The column density of this doubly deuterated isotopolog is roughly a factor of five higher than what would be extrapolated from the un- and sinly deuterated isotopologs, as frequently observed in this as well as other sources.\\

dms

anonymous@undisclosed.example.com (Anonymous) — Wed, 26 Feb 2025 13:46:25 +0000

2025/02/26 14:24		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/adafa7\|On the Abiotic Origin of Dimethyl Sulfide: Discovery of Dimethyl Sulfide in the Interstellar Medium]]\\		[[https://doi.org/10.3847/2041-8213/adafa7\|On the Abiotic Origin of Dimethyl Sulfide: Discovery of Dimethyl Sulfide in the Interstellar Medium]]\\
	//Astrophys. J. Lett.// 980, Art. No. L37 (2025).\\		//Astrophys. J. Lett.// 980, Art. No. L37 (2025).\\
-	Dimethyl sulfide, (CH<sub>3</sub>)<sub>2</sub>S, was identified in the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes. Several //b//-type lines with 2 ≤ //J// ≤ 9, //K<sub>c</sub>// ≤ 4, and with unresolved internal rotation splitting were assigned with reasonable signal-to-noise ratios, but a number of these are blended to different amounts. Both molecules have excitation temperatures of about 15 K, and propene has an about three times higher column density than isobutene. Isobutene is only the second molecules with a branched carbon chain after isopropyl cyanide.\\	+	Dimethyl sulfide, (CH<sub>3</sub>)<sub>2</sub>S, was identified in the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes. Several //b//-type lines with 2 ≤ //J// ≤ 9, //K<sub>a</sub>// ≤ 4, and with unresolved internal rotation splitting were assigned with reasonable signal-to-noise ratios, but a number of these are blended to different amounts. The excitation temperatures was determined as 13 ± 3 K. Its column density is about a factor of 30 lower than than of its oxigen homolog dimethyl ether and about a factor of 1.6 lower than its ethanethiol isomer.\\
	\\		\\

Line 13:		Line 13:

	----		----
-

ecp

anonymous@undisclosed.example.com (Anonymous) — Wed, 27 Sep 2023 13:57:14 +0000

2022/08/03 10:51		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202244399\|Discovery of fulvenallene in TMC-1 with the QUIJOTE line survey]]\\		[[https://doi.org/10.1051/0004-6361/202244399\|Discovery of fulvenallene in TMC-1 with the QUIJOTE line survey]]\\
	//Astron. Astrophys.// 663, Art. No. L9 (2022).\\		//Astron. Astrophys.// 663, Art. No. L9 (2022).\\
-	The molecular line survey was carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. Ethenylidenecyclopentadiene, aka fulvenallene, was detected in several //a//-type transitions having 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 3. A considerable fraction of the lines is not or only slightly blended. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived through a rotation diagram. The column densities (in units of 10<sup>10</sup> cm<sup>−2</sup>) of the butenenitriles is about 5, 13, 10, 7, and 8 for the //E//-1-, //Z//-1-, 2-, //syn//-3-, and //gauche//-3-forms, respectively, compared to ~4 × 10<sup>13</sup> cm<sup>−2</sup> for propene. The combined cyanopropenes are much less abundant in relation to its parent hydrocarbon compared to other detected cyanide derivatives. It is also noteworthy to point out that the abundances among the cyanopropenes do not at all reflect relative energies among these species.\\	+	The molecular line survey was carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. Ethenylidenecyclopentadiene, aka fulvenallene, was detected in several //a//-type transitions having 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 3. A considerable fraction of the lines is not or only slightly blended. A value of //T//<sub>rot</sub> = 9 ± 1 K was derived through a rotation diagram. Its column density is only about a factor of 4.5 lower than that of cyclopentadiene and about a factor of 11 to 26 of what has been estimated for ethene.\\
		+	\\

	----		----

eme

anonymous@undisclosed.example.com (Anonymous) — Tue, 18 Jan 2022 11:35:21 +0000

2020/03/09 10:38		current
Line 31:		Line 31:
	S. Manigand, J. K. Jørgensen, H. Calcutt, H. S. P. Müller, N. F. W. Ligterink, A. Coutens, M. N. Drozdovskaya, E. F. van Dishoeck, and S. F. Wampfler\\		S. Manigand, J. K. Jørgensen, H. Calcutt, H. S. P. Müller, N. F. W. Ligterink, A. Coutens, M. N. Drozdovskaya, E. F. van Dishoeck, and S. F. Wampfler\\
	reported on\\		reported on\\
-	[[https://doi.org/10.1051/0004-6361/201834417\|The ALMA-PILS Survey: Inventory of Complex Organic Molecules towards IRAS 16293–2422 A]]\\	+	[[https://doi.org/10.1051/0004-6361/201936299\|The ALMA-PILS Survey: Inventory of Complex Organic Molecules towards IRAS 16293–2422 A]]\\
	//Astron. Astrophys.// 635, Art. No. A48 (2020).\\		//Astron. Astrophys.// 635, Art. No. A48 (2020).\\
		+	They found ethyl methyl ether toward IRAS 16293–2422 B in this context.

etcn

anonymous@undisclosed.example.com (Anonymous) — Thu, 17 Mar 2022 08:39:40 +0000

ethanimin

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:43:48 +0000

ethanolamin

anonymous@undisclosed.example.com (Anonymous) — Tue, 05 Oct 2021 13:13:10 +0000

2021/05/31 10:39		current
Line 5:		Line 5:
	[[https://doi.org/10.1073/pnas.2101314118\|Discovery in space of ethanolamine, the simplest phospholipid head group]]\\		[[https://doi.org/10.1073/pnas.2101314118\|Discovery in space of ethanolamine, the simplest phospholipid head group]]\\
	//Proc. Natl. Acad. Sci. USA// 118 (2021), Art. No. e2101314118.\\		//Proc. Natl. Acad. Sci. USA// 118 (2021), Art. No. e2101314118.\\
-	14 //a//-type rotational transitions of HOCH<sub>2</sub>CH<sub>2</sub>NH<sub>2</sub> with 3 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 4 were unblended or slightly blended, many more were blended considerably. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. The unblended lines were quite reasonably well employing an LTE fit with //T//<sub>rot</sub> = 10.7 ± 0.7 K. The moderate signal-to-noise ratio limits the quality of this fit somewhat.\\	+	14 //a//-type rotational transitions of HOCH<sub>2</sub>CH<sub>2</sub>NH<sub>2</sub> with 3 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 4 were unblended or slightly blended, many more were blended considerably. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. The unblended lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> = 10.7 ± 0.7 K. The moderate signal-to-noise ratio limits the quality of this fit somewhat.\\
		+	IRAM issued a [[https://www.iram-institute.org/EN/news/2021/206.html\|press release]].\\

	----		----

ethendiol

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Apr 2022 14:37:48 +0000

2022/04/25 16:25		current
Line 3:		Line 3:
	V. M. Rivilla, L. Colzi, I. Jiménez-Serra, J. Martín-Pintado, A. Megías, M. Melosso, L. Bizzocchi, Á. López-Gallifa, A. Martínez-Henares, S. Massalkhi, B. Tercero, P. de Vicente, J.-C. Guillemin, J. G. de la Concepción, F. Rico-Villas, S. Zeng, S. Martín, M. A. Requena-Torres, F. Tonolo, S. Alessandrini, L. Dore, V. Barone, and C. Puzzarini\\		V. M. Rivilla, L. Colzi, I. Jiménez-Serra, J. Martín-Pintado, A. Megías, M. Melosso, L. Bizzocchi, Á. López-Gallifa, A. Martínez-Henares, S. Massalkhi, B. Tercero, P. de Vicente, J.-C. Guillemin, J. G. de la Concepción, F. Rico-Villas, S. Zeng, S. Martín, M. A. Requena-Torres, F. Tonolo, S. Alessandrini, L. Dore, V. Barone, and C. Puzzarini\\
	reported on\\		reported on\\
		+	**[[https://doi.org/10.3847/2041-8213/ac6186\|Precursors of the RNA World in Space: Detection of (Z)-1,2-ethenediol in the Interstellar
		+	Medium, a Key Intermediate in Sugar Formation]]**\\
		+	//Astrophys. J. Lett.// 920 (2021), Art. No. L27.\\
		+	The molecule was identified through nine lines of which four appear to be unblended, four are partially blended, and one is fully blended, but the molecule accounts for a large fraction of the emission. Each line consists of a pair of //a//-type rotation-tunneling transitions having 2 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 2. The molecule is the enolic and less stable form of glycolaldehyde which is only ~5.2 times more abundant.\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 04, 2022
		+
		+	----

ethenimin

anonymous@undisclosed.example.com (Anonymous) — Mon, 03 Jan 2022 10:53:51 +0000

2022/01/03 11:40		current
Line 1:		Line 1:
-	===== On Etheneimine in the ISM =====	+	===== On Ethenimine in the ISM =====

-	The detection of etheneimine, aka ketenimine, in Sgr B2(N-LMH) has been reported very recently:\\	+	The detection of ethenimine, aka ketenimine, in Sgr B2(N-LMH) has been reported very recently:\\
	F. J. Lovas, J. M. Hollis, A. R. Remijan,and P. R. Jewell,\\		F. J. Lovas, J. M. Hollis, A. R. Remijan,and P. R. Jewell,\\
	[[https://doi.org/10.1086/506324\|Detection of Ketenimine (CH<sub>2</sub>CNH) in Sgr B2(N) Hot Cores]]\\		[[https://doi.org/10.1086/506324\|Detection of Ketenimine (CH<sub>2</sub>CNH) in Sgr B2(N) Hot Cores]]\\
	//Astrophys. J.// 645, L137–L140 (2006).\\		//Astrophys. J.// 645, L137–L140 (2006).\\
-	Three lines have been detected thus far of which one line may show partially resolved hyperfine structure.	+	Three lines have been detected thus far with the 100 m GBT of which one line at 4.9 GHz probably shows partially resolved hyperfine structure.
	The proposed single state temperature of 65 K appears to be peculiar and may indicate non-thermal population.		The proposed single state temperature of 65 K appears to be peculiar and may indicate non-thermal population.

ethylformiat

anonymous@undisclosed.example.com (Anonymous) — Wed, 04 Mar 2026 10:34:18 +0000

ethynylcyclopropenylidene

anonymous@undisclosed.example.com (Anonymous) — Tue, 18 May 2021 13:26:26 +0000

2021/05/18 15:00		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202141156\|Pure hydrocarbon cycles in TMC-1: Discovery of ethynylcyclopropenylidene, cyclopentadiene, and indene]]\\		[[https://doi.org/10.1051/0004-6361/202141156\|Pure hydrocarbon cycles in TMC-1: Discovery of ethynylcyclopropenylidene, cyclopentadiene, and indene]]\\
	//Astron. Astrophys.// 649, Art. No. L15 (2021).\\		//Astron. Astrophys.// 649, Art. No. L15 (2021).\\
-	Ethynylcyclopropenylidene, //c//-C<sub>3</sub>HCCH, was identified through 12 unblended or slightly blended mostly //b//-type transitions with 1 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of //T//<sub>rot</sub> = 8 ± 3 K was derived through a rotation diagram, but the model is more compatible with 10 K. The column density of butenyne is about a factor of 4.5 higher than that of the isoelectronic allenyl cyanide. It is, in addition, similar to that of butenyne, a factor of 5 lower than that of the methyldiacetylene isomer (aka butadienyne), and a factor of 10 lower than that of methylacetylene (aka propyne).\\	+	Ethynylcyclopropenylidene, //c//-C<sub>3</sub>HCCH, was identified through 12 unblended or slightly blended mostly //b//-type transitions with 1 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of //T//<sub>rot</sub> = 8 ± 3 K was derived through a rotation diagram, but the model is more compatible with 10 K. The column density of //c//-C<sub>3</sub>HCCH is about a factor of 190 lower than that of //c//-C<sub>3</sub>H<sub>2</sub> and about a factor of 20 lower than that of //c//-C<sub>3</sub>H.\\

etnco

anonymous@undisclosed.example.com (Anonymous) — Tue, 08 Mar 2022 13:58:01 +0000

2021/10/05 15:13		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202141989\|First detection of C<sub>2</sub>H<sub>5</sub>NCO in the ISM and search of other isocyanates towards the G+0.693−0.027 molecular cloud]]\\		[[https://doi.org/10.1051/0004-6361/202141989\|First detection of C<sub>2</sub>H<sub>5</sub>NCO in the ISM and search of other isocyanates towards the G+0.693−0.027 molecular cloud]]\\
	//Astron. Astrophys.// 654 (2021), Art. No. L1.\\		//Astron. Astrophys.// 654 (2021), Art. No. L1.\\
-	8 rotational transitions of C<sub>2</sub>H<sub>5</sub>NCO, all but one //a//-types, with 5 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 2 were covered in the course of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm. Five transitions are unblended or only slightly blended. The lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> = 10 ± 2 K.	+	8 rotational transitions of C<sub>2</sub>H<sub>5</sub>NCO, all but one //a//-types, with 5 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 2 were covered in the course of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm. Five transitions are unblended or only slightly blended. The lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> = 10 ± 2 K. The column density ratio of methyl to ethyl isocyanate was estimated to be about 8.

	----		----

-	Contributor(s): H. S. P. Müller; 20, 2021	+	Contributor(s): H. S. P. Müller; 10, 2021

	----		----

etoh

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:47:36 +0000

etsh

anonymous@undisclosed.example.com (Anonymous) — Fri, 07 May 2021 13:49:02 +0000

2021/05/07 15:38		current
Line 19:		Line 19:
	C<sub>2</sub>H<sub>5</sub>SH]]**\\		C<sub>2</sub>H<sub>5</sub>SH]]**\\
	//Astrophys. J. Lett.// 912 (2021), Art. No. L11.\\		//Astrophys. J. Lett.// 912 (2021), Art. No. L11.\\
-	This is the first unumbiguous detection of ethanethiol in the ISM. Ten rotational transitions of the lower-lying gauche conformer with 3 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 3 were reported and shown, of which six were unblended or marginally blended, four lines were more blended. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. All but one of the blended lines were modeled quite well employing and LTE fit with //T//<sub>rot</sub> ≈ 10 K. The column density of methanethiol is a factor of ∼16 higher, that of ethanol a factor of ∼15 higher.\\	+	This is the first unumbiguous detection of ethanethiol in the ISM. Ten lines of the lower-lying gauche conformer with 3 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 3 were reported and shown, of which six were unblended or marginally blended, four lines were more blended. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. All but one of the blended lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> ≈ 10 K. The column density of methanethiol is a factor of ∼16 higher, that of ethanol a factor of ∼15 higher.\\

fec

anonymous@undisclosed.example.com (Anonymous) — Fri, 24 Nov 2023 12:40:44 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Iron Carbide, FeC, in Circumstellar Environments =====
	+
	+	L. A. Koelemay and L. M. Ziurys\\
	+	reported on\\
	+	[[https://doi.org/10.3847/2041-8213/ad0899\|Elusive Iron: Detection of the FeC Radical (X<sup>3</sup>Δ<sub>i</sub>) in the Envelope of IRC+10216]]\\
	+	//Astrophys. J. Lett.// 958, Art. No. L6 (2023).\\
	+	Dedicated observations of CW Leonis with the ARO SMT as well as observations from a line survey at 2 mm with the ARO 12 m dish at Kitt Peak in the regions of the <sup>3</sup>Δ<sub>3</sub>, //J"// = 5, 4, and 3 transitions of FeC. The derived column density is nearly the same as for FeCN.\\
	+	\\
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 11, 2023
	+
	+	----

feo

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:00:16 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Tentative Detection of FeO in the Interstellar Medium =====
	+
	+	FeO had been identified previously by its electronic spectrum in stellar atmospheres. Very recently, its lowest energy //J// = 5 – 4 transition has been detected in the ISM towards Sgr B2 M:\\
	+	C. M. Walmsley, R. Bachiller, G. Pineau des Forêts, and P. Schilke,\\
	+	[[https://doi.org/10.1086/339694\|Detection of FeO toward Sagittarius B2]]\\
	+	//Astrophys. J.// 566, L109–L112 (2002).\\
	+	Since this is the only transition identified positively the detection is viewed as tentative in that paper.
	+
	+	More recently, the spatial distribution of this transition has been investigated:\\
	+	R. S. Furuya, C. M. Walmsley, K. Nakanishi, P. Schilke, and R. Bachiller,\\
	+	[[https://doi.org/10.1051/0004-6361:20031304\|Interferometric observations of FeO towards Sagittarius B2]]\\
	+	//Astron. Astrophys.// 409, L21–L24 (2003).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 09, 2003
	+
	+	----
	+

formamid

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 20:03:39 +0000

formic_acid

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:09:07 +0000

2019/10/23 17:06		current
Line 3:		Line 3:
	Formic acid, HC(O)OH, seems to be a fairly typical hot core molecule that is quite abundant. The 1<sub>11</sub> – 1<sub>10</sub> transition of this molecule was the first one to be detected – toward the massive star-forming region Sgr B2 near the Galactic center:\\		Formic acid, HC(O)OH, seems to be a fairly typical hot core molecule that is quite abundant. The 1<sub>11</sub> – 1<sub>10</sub> transition of this molecule was the first one to be detected – toward the massive star-forming region Sgr B2 near the Galactic center:\\
	B. Zuckerman, J. A. Ball, and C. A. Gottlieb,\\		B. Zuckerman, J. A. Ball, and C. A. Gottlieb,\\
-	[[http://cdsads.u-strasbg.fr/doi/10.1086/180663\|Microwave Detection of Interstellar Formic Acid]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1971ApJ...163L..41Z\|Microwave Detection of Interstellar Formic Acid]]\\
	//Astrophys. J.// 163, L41–L45 (1971);\\		//Astrophys. J.// 163, L41–L45 (1971);\\
	the detection of a second transition was reported by\\		the detection of a second transition was reported by\\
	G. Winnewisser and E. Churchwell,\\		G. Winnewisser and E. Churchwell,\\
-	[[http://adsabs.harvard.edu/doi/10.1086/181890\|Detection of Formic Acid in Sagittarius B2 by its 2<sub>11</sub> – 2<sub>12</sub> Transition]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1975ApJ...200L..33W\|Detection of Formic Acid in Sagittarius B2 by its 2<sub>11</sub> – 2<sub>12</sub> Transition]]\\
	//Astrophys. J.// 200, L33–L36 (1975).		//Astrophys. J.// 200, L33–L36 (1975).

fullerene

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 08:04:08 +0000

2019/04/24 15:28		current
Line 51:		Line 51:

	J. Cami, J. Bernard-Salas, E. Peeters, and S. E. Malek,\\		J. Cami, J. Bernard-Salas, E. Peeters, and S. E. Malek,\\
-	reported on [[http://dx.doi.org/10.1126/science.1192035\|Detection of C<sub>60</sub> and C<sub>70</sub> in a Young Planetary Nebula]],\\	+	reported on\\
		+	[[https://doi.org/10.1126/science.1192035\|Detection of C<sub>60</sub> and C<sub>70</sub> in a Young Planetary Nebula]],\\
	//Science// 659, 1180–1182 (2010).\\		//Science// 659, 1180–1182 (2010).\\
	They have used archival //Spitzer// data of Tc 1. The C<sub>60</sub> features at 17.4 and 18.9 μm overlap with slightly weaker C<sub>70</sub> features at similar positions. The 8.5 μm feature of C<sub>60</sub> was also observed, the one near 7.0 μm is overlapped by a much stronger Ar<sup>+</sup> line. Weak C<sub>70</sub> features at 12.5, 14.8, 15.6, and 21.8 μm seem to be free from overlap.\\		They have used archival //Spitzer// data of Tc 1. The C<sub>60</sub> features at 17.4 and 18.9 μm overlap with slightly weaker C<sub>70</sub> features at similar positions. The 8.5 μm feature of C<sub>60</sub> was also observed, the one near 7.0 μm is overlapped by a much stronger Ar<sup>+</sup> line. Weak C<sub>70</sub> features at 12.5, 14.8, 15.6, and 21.8 μm seem to be free from overlap.\\

glycin

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:13:29 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Quest for Glycine, Aminoacetic Acid, in the ISM =====
	+
	+	Aminoacetic acid, better known as glycine, has been sought for in the interstellar medium for a long time. Very recently, there has been a report on the detection of glycine in Sgr B2(N-LMH), Orion KL, and W51 e1/e2:\\
	+	Y.-J. Kuan, S. B. Charnley, H.-C. Huang, W.-L. Tseng, and Z. Kisiel,\\
	+	[[https://doi.org/10.1086/375637\|Interstellar Glycine]]\\
	+	//Astrophys. J.// 593, 848–867 (2003).
	+
	+	This paper has caused quite a stir in the astronomical community, in particular if one considers the following paper:\\
	+	J. M. Hollis, J. A. Pedelty, L. E. Snyder, P. R. Jewell, F. J. Lovas, P. Palmer, and S.-Y. Liu,\\
	+	[[https://doi.org/10.1086/373945\|A Sensitive Very Large Array Search for Small-Scale Glycine Emission toward OMC-1]]\\
	+	//Astrophys. J.// 588, 353–359 (2003).
	+
	+	It should be noted that the number of supposedly positively identified transitions reported by Kuan //et al.// is fairly large. Therefore, the report may be considered quite convincing.\\
	+	However, it was brought to our attention that there seem to be some inconsistencies in the intensities of the lines. In particular, some of the observed lines seem to be too weak by a substantial amount that seems to be incompatible with the derived abundances and rotational temperatures. This may cast doubt on the derived abundances and possibly even on the interstellar detection.\\
	+	At the moment it appears as if the publication of these reported inconsistencies will not settle the dispute of the glycine detection.
	+
	+	The paper alluded to in the previous paragraph is:\\
	+	L. E. Snyder, F. J. Lovas, J. M. Hollis, D. N. Friedel, P. R. Jewell, A. Remijan, V. V. Ilyushin, E. A. Alekseev, and S. F. Dyubko,\\
	+	[[https://doi.org/10.1086/426677\|A Rigorous Attempt to Verify Interstellar Glycine]]\\
	+	//Astrophys. J.// 619, 914–930 (2005).
	+
	+	Overall, we would recommend the detection of glycine to be taken very cautiously.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2004
	+
	+	----
	+

glycol

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:53:31 +0000

2019/04/24 16:26		current
Line 3:		Line 3:
	There is a report in the literature on detection of ethanediol, aka ethylene glycol, or briefly glycol, in Sgr B2(N-LMH):\\		There is a report in the literature on detection of ethanediol, aka ethylene glycol, or briefly glycol, in Sgr B2(N-LMH):\\
	J. M. Hollis, F. J. Lovas, P. R. Jewell, and L. H. Coudert,\\		J. M. Hollis, F. J. Lovas, P. R. Jewell, and L. H. Coudert,\\
-	[[http://dx.doi.org/10.1086/341148\|Interstellar Antifreeze: Ethylene Glycol]]\\	+	[[https://doi.org/10.1086/341148\|Interstellar Antifreeze: Ethylene Glycol]]\\
	//Astrophys. J.// 571, L59–L62 (2002).\\		//Astrophys. J.// 571, L59–L62 (2002).\\
	Because of the small number of lines and possible line overlap the detection should be viewed with some caution by itself.		Because of the small number of lines and possible line overlap the detection should be viewed with some caution by itself.
Line 9:		Line 9:
	More recently, two transition with complex velocity components have been detected in the centimeter range toward Sgr B2(N-LMH) employing the GBT:\\		More recently, two transition with complex velocity components have been detected in the centimeter range toward Sgr B2(N-LMH) employing the GBT:\\
	J. M. Hollis,\\		J. M. Hollis,\\
-	[[hollis_asilomar.pdf\|Complex Molecules and the GBT: Is Isomerism the Key ?]],\\	+	**{{ :pdfs:hollis_asilomar.pdf \|Complex Molecules and the GBT: Is Isomerism the Key ?}}**,
	Contribution at the IAU Symposium 231, Astrochemistry throughout the Universe, Asilomar, CA.\\		Contribution at the IAU Symposium 231, Astrochemistry throughout the Universe, Asilomar, CA.\\
	While it is hard to say that the detection is beyond doubt, these two lines render the detection quite secure – mainly because the line density at these lower frequencies is fairly small.		While it is hard to say that the detection is beyond doubt, these two lines render the detection quite secure – mainly because the line density at these lower frequencies is fairly small.
Line 47:		Line 48:

	Contributor(s): H. S. P. Müller; 12, 2005; 07, 2012; 04, 2015; 11, 2016		Contributor(s): H. S. P. Müller; 12, 2005; 07, 2012; 04, 2015; 11, 2016
-

	----		----

glycolaldehyd

anonymous@undisclosed.example.com (Anonymous) — Wed, 02 Jun 2021 12:36:38 +0000

glykolamid

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Aug 2023 10:45:13 +0000

2023/08/24 12:32		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/ace977\|First Glycine Isomer Detected in the Interstellar Medium: Glycolamide (NH2C(O)CH2OH)]]\\		[[https://doi.org/10.3847/2041-8213/ace977\|First Glycine Isomer Detected in the Interstellar Medium: Glycolamide (NH2C(O)CH2OH)]]\\
	//Astrophys. J. Lett.// 953, Art. No. L20 (2023).\\		//Astrophys. J. Lett.// 953, Art. No. L20 (2023).\\
-	The molecule was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes.	+	The molecule was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes. The transitions cover 31 to 98 GHz with 1 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 5. Some lines are unblended, slightly blended, or the peak of the line is at most slightly blended. Some further lines are blended more substantially. The glycolaldehyde/glycolamide ratio is ∼15, while the ethanol/ethanolamine ratio is ∼40.\\
	\\		\\

h2c_ns

anonymous@undisclosed.example.com (Anonymous) — Thu, 17 Nov 2022 11:58:49 +0000

2022/11/17 12:57		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202140642\|TMC-1, the starless core sulfur factory: Discovery of NCS, HCCS, H<sub>2</sub>CCS, H<sub>2</sub>CCCS, and C<sub>4</sub>S and detection of C<sub>5</sub>S]]\\		[[https://doi.org/10.1051/0004-6361/202140642\|TMC-1, the starless core sulfur factory: Discovery of NCS, HCCS, H<sub>2</sub>CCS, H<sub>2</sub>CCCS, and C<sub>4</sub>S and detection of C<sub>5</sub>S]]\\
	//Astron. Astrophys.// 648, Art. No. L3 (2021).\\		//Astron. Astrophys.// 648, Art. No. L3 (2021).\\
-	The ethenthione, H<sub>2</sub>C<sub>2</sub>S, and propadienthione, H<sub>2</sub>C<sub>3</sub>S, molecules were identified through 6 and 7 //a//-type transitions, respectively, with //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. The column density of H<sub>2</sub>C<sub>2</sub>S is about a factor of 100 lower than that of H<sub>2</sub>CS and about a factor of two higher than that of H<sub>2</sub>C<sub>3</sub>S.\\	+	The ethenthione, H<sub>2</sub>C<sub>2</sub>S, and propadienthione, H<sub>2</sub>C<sub>3</sub>S, molecules were identified through 6 and 7 //a//-type transitions, respectively, with //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. The column density of H<sub>2</sub>C<sub>2</sub>S is about a factor of 100 lower than that of H<sub>2</sub>CS and about a factor of two higher than that of H<sub>2</sub>C<sub>3</sub>S.\\

h2c3h-plus

anonymous@undisclosed.example.com (Anonymous) — Thu, 10 Aug 2023 13:15:11 +0000

2023/07/27 13:55		current
Line 1:		Line 1:
-	===== On the Detection of Propadieneylium, H2C3H+, in Space =====	+	===== On the Detection of Propadienylium, H2C3H+, in Space =====

	W. G. D. P. Silva, J. Cernicharo, S. Schlemmer, N. Marcelino, J.-C. Loison, M. Agúndez, D. Gupta, V. Wakelam, S. Thorwirth, C. Cabezas, B. Tercero, J. L. Doménech, R. Fuentetaja, W.-J. Kim, P. de Vicente, and O. Asvany\\		W. G. D. P. Silva, J. Cernicharo, S. Schlemmer, N. Marcelino, J.-C. Loison, M. Agúndez, D. Gupta, V. Wakelam, S. Thorwirth, C. Cabezas, B. Tercero, J. L. Doménech, R. Fuentetaja, W.-J. Kim, P. de Vicente, and O. Asvany\\
	announced the\\		announced the\\
-	[[https://doi.org/10.1051/0004-6361/201527460\|Discovery of H2CCCH+ in TMC-1]],\\	+	[[https://doi.org/10.1051/0004-6361/202347174\|Discovery of H2CCCH+ in TMC-1]],\\
	//Astron. Astrophys.// 676, Art. No. L1 (2023)\\		//Astron. Astrophys.// 676, Art. No. L1 (2023)\\
		+	Three //a//-type transitions with //J// = 2 − 1 around 38 GHz and one transition near 95.9 GHz were detected with good signal-to-noise ratio in the course of the QUIJOTE line survey carried out with the Yebes 40 m and IRAM 30 m dishes. Only one transition was marginally blended. The molecular cation is only about a factor of three less abundant than the unprotonated propadienylidene.\\
		+	\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 07, 2023
		+
		+	----
		+

h2c3n

anonymous@undisclosed.example.com (Anonymous) — Thu, 10 Aug 2023 13:24:11 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Cyanovinyl Radicals in Space =====
	+
	+	C. Cabezas, J. Tang, M. Agúndez, K. Seiki, Y. Sumiyoshi, Y. Ohshima, B. Tercero, N. Marcelino, R. Fuentetaja, P. de Vicente, Y. Endo, and J. Cernicharo\\
	+	announced the \\
	+	[[https://doi.org/10.1051/0004-6361/202347385\|Laboratory and Astronomical Discovery of the Cyanovinyl Radical H2CCCN]],\\
	+	//Astron. Astrophys.// 676, Art. No. L1 (2023)\\
	+	Two //a//-type transitions with //J// = 4 − 3 and 5 − 4 and //K<sub>a</sub>// = 0 around 34.9 and 43.65 GHz were detected in several fine and hyperfine components in the course of the QUIJOTE line survey carried out with the Yebes 40 m dish. Some of the lines were blended to different degrees. A rotational temperature of ~6 K was adopted. The molecule is about a factor of 26 less abundant than vinyl cyanide.\\
	+	\\
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 08, 2023
	+
	+	----
	+

h2c5

anonymous@undisclosed.example.com (Anonymous) — Tue, 15 Jun 2021 10:34:41 +0000

2021/06/15 12:33		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202141274\|Cumulene carbenes in TMC-1: Astronomical discovery of //l//-H<sub>2</sub>C<sub>5</sub>]]\\		[[https://doi.org/10.1051/0004-6361/202141274\|Cumulene carbenes in TMC-1: Astronomical discovery of //l//-H<sub>2</sub>C<sub>5</sub>]]\\
	//Astron. Astrophys.// 650, Art. No. L9 (2021).\\		//Astron. Astrophys.// 650, Art. No. L9 (2021).\\
-	The molecule was identified through 11 unblended to somewhat blended //a//-type transitions with 6 ≤ //J// ≤ 10 and //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of about 10 K was derived for //T//<sub>rot</sub>. The column density ratios of the //l//-H<sub>2</sub>C<sub>//n//</sub> molecules with //n// = 3 to 6 is about 344 : 561 : 1 : 4.4; reflecting the decrease with //n// on one hand and the lower column densities for //n// being odd on the other hand.\\	+	The molecule was identified through 11 unblended to somewhat blended //a//-type transitions with 6 ≤ //J// ≤ 10 and //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of about 10 K was derived for //T//<sub>rot</sub>. The column density ratios of the //l//-H<sub>2</sub>C<sub>//n//</sub> molecules with //n// = 3 to 6 is about 344 : 561 : 1 : 4.4, reflecting the decrease with //n// on one hand and the lower column densities for //n// being odd on the other hand.\\

		+
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 06, 2021
		+
		+	----

h2ccn

anonymous@undisclosed.example.com (Anonymous) — Fri, 26 Feb 2021 14:50:04 +0000

2021/02/26 15:41		current
Line 17:		Line 17:
	C. Cabezas, Y. Endo, E. Roueff, N. Marcelino, M. Agúndez, B. Tercero, and J. Cernicharo\\		C. Cabezas, Y. Endo, E. Roueff, N. Marcelino, M. Agúndez, B. Tercero, and J. Cernicharo\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1051/0004-6361:202040210\|Space and laboratory observation of the deuterated cyanomethyl radical HDCCN]]\\	+	[[https://doi.org/10.1051/0004-6361/202040210\|Space and laboratory observation of the deuterated cyanomethyl radical HDCCN]]\\
-	//Astron. Astrophys.// 646, Art. No. L1 (2021).	+	//Astron. Astrophys.// 646, Art. No. L1 (2021).\\
		+	The 2<sub>02</sub> − 1<sub>01</sub> transition near 37.49 GHz with fine and hyperfine structure splitting was detected toward TMC-1 using the Yebes 40 m radio telescope in the course of a molecular line survey. The derived H<sub>2</sub>CCN to HDCCN ratio is 20 ± 4, i.e., ~40 per H atom, quite normal for TMC-1.


	----		----

-	Contributor(s): H. S. P. Müller; 12, 2003; 07, 2011	+	Contributor(s): H. S. P. Müller; 12, 2003; 07, 2011; 02, 2021

	----		----

h2cco

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:11:42 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on the Detection of Ethenone in the ISM =====
	+
	+	Ethenone, H<sub>2</sub>CCO, aka ketene, had been identified first in spectra recorded toward Sgr B2(OH) by\\
	+	B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1977ApJ...213L..75T\|Microwave Detection of Interstellar Ketene]]\\
	+	//Astrophys. J.// 213, L75–L79 (1977).\\
	+	The NRAO 11 m telecope was employed to identify three //K<sub>a</sub>// = 1 transitions with //J'// = 4 and 5. The fourth transition and the two //K<sub>a</sub>// = 0 transitions were detected tentatively around 81 and 101 GHz.
	+
	+	Evidence for the //J'// = 4, //K<sub>a</sub>// = 0 and 1 transitions were found in Orion A by:\\
	+	L. E. B. Johansson, C. Andersson, J. Eldér, P. Friberg, Å. Hjalmarson, B. Höglund, W. M. Irvine, H. Olofsson, and G. Rydbeck,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1984A%26A...130..227J\|Spectral Scan of Orion A and IRC +10216 from 72 to 91 GHz]]\\
	+	//Astron. Astrophys.// 130, 227–256 (1984).
	+
	+	It is also fairly abundant in dark clouds:\\
	+	M. Ohishi, K. Kawaguchi, N. Kaifu, W. M. Irvine, Y. C. Minh, S. Yamamoto, S. Saito,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1991ASPC...16..387O\|The Ortho to Para Ratio for Ketene in TMC-1]]\\
	+	//ASP Conf. Ser.// 16, 387–391 (1991).
	+
	+	It was also found in three translucent clouds (CB 17 CB 24, and CB 228):\\
	+	B. E. Turner, R. Terzieva, and E. Herbst,\\
	+	[[https://doi.org/10.1086/307300\|The Physics and Chemistry of Small Translucent Molecular Clouds. XII. More Complex Species Explainable by Gas-Phase Processes]]\\
	+	//Astrophys. J.// 518, 699–732 (1999).
	+
	+	J. K. Jørgensen, H. S. P. Müller, H. Calcutt, A. Coutens, M. N. Drozdovskaya, K. I. Öberg, M. V. Persson, V. Taquet, E. F. van Dishoeck, and S. F. Wampfler\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/201731667\|The ALMA-PILS Survey: Isotopic Composition of Oxygen-containing Complex Organic Molecules toward IRAS 16293–2422B]]\\
	+	//Astron. Astrophys.// 620, Art. No. A170 (2018).\\
	+	The results were obtained in the course of a line survey of the solar-type protostellar binary IRAS 16293–2422 with ALMA covering the frequency range 329.1–362.9 GHz. The authors only investigated source B. They detected for the first time both <sup>13</sup>C isotopomers as well as the mono-deuterated isotopolog. The D/H ratio per H atom is about 0.02 (the HDCCO/H<sub>2</sub>CCO ratio is about 0.04). Many lines of the main isotopic species were optically thick; the local ISM <sup>12</sup>C/<sup>13</sup>C ratio of 68 was assumed. The <sup>18</sup>O and the doubly deuterated isotopologs were near the detection limit and not identified with certainty. Ketene is among the molecules with colder rotational temperatures of around 125 K in that hot corino.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2006; 03, 2012; 01, 2019
	+
	+	----
	+

h2cl-plus

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:40:27 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Chloronium, H2Cl+, in the Interstellar Medium =====
	+
	+	Chloronium has been detected in absorption with the //Herschel// satellite toward the star-forming regions NGC 6334I and Sagittarius B2(S):\\
	+	D. C. Lis, J. C. Pearson, D. A. Neufeld, et al.\\
	+	[[https://doi.org/10.1051/0004-6361/201014959\|//Herschel///HIFI Discovery of Interstellar Chloronium (H<sub>2</sub>Cl<sup>+</sup>)]]\\
	+	//Astron. Astrophys.// 521, (2010) Art. No. L9.\\
	+	Three transitions have been detected toward NGC 6334I which show broadening by Cl hyperfine splitting and no recognizable absorption caused by spiral arm clouds. The 2<sub>12</sub> –1<sub>01</sub> transition of //ortho//-H<sub>2</sub>Cl<sup>+</sup> has been observed near 781.6 and 780.05 GHz for the <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs, respectively. The 1<sub>11</sub> –0<sub>00</sub> transition of //para//-H<sub>2</sub><sup>35</sup>Cl<sup>+</sup> was observed near 485.4 GHz.\\
	+	The absorption features near 485.4 and 780.05 GHz were both affected by emission features from dimethyl ether. A preliminary model for this molecule permitted accounting for these emmsion features in the analyses. This is a clear example that features by so-called "weed" species can affect "flowers" even in the case of //Herschel// observations. The recent report on the rotational spectroscopy of dimethyl ether by C. P. Endres et al., //Astron. Astrophys.// 504, (2009) 635, were instrumental.\\
	+	The 1<sub>11</sub> –0<sub>00</sub> transition of //para//-H<sub>2</sub><sup>35</sup>Cl<sup>+</sup>, observed toward Sgr B2(S), displays absorption features of spiral arm clouds.
	+
	+	More recently, H<sub>2</sub>Cl<sup>+</sup> has turned out to be rather widespread. The 1<sub>11</sub> –0<sub>00</sub> transition of the //para// species was observed with the //Herschel// satellite for both <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs in absorption toward the strong contiunuum sources W31C and Sgr A (+50 km/s cloud). The transition was seen in emission in Orion S and in the photon-dominated region Orion Bar by:\\
	+	D. A. Neufeld, E. Roueff, R. L. Snell, et al.\\
	+	[[https://doi.org/10.1088/0004-637X/748/1/37\|//Herschel// Observations of Interstellar Chloronium]]\\
	+	//Astrophys. J.// 748, (2012) Art. No. 37.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2010; 3, 2012
	+
	+	----
	+

h2cn

anonymous@undisclosed.example.com (Anonymous) — Wed, 13 Oct 2021 12:19:03 +0000

2021/10/13 14:16		current
Line 12:		Line 12:
	[[https://doi.org/10.1051/0004-6361/201935010\|Isocyanogen Formation in the Cold Interstellar Medium]],\\		[[https://doi.org/10.1051/0004-6361/201935010\|Isocyanogen Formation in the Cold Interstellar Medium]],\\
	//Astron. Astrophys.// 625, art. no. A91 (2019).\\		//Astron. Astrophys.// 625, art. no. A91 (2019).\\
-	A molecular line survey of the prestellar cor L1544 between 71.74 and 115.87 GHz was carried out with the IRAM 30 m telescope. Methyleneamidogen was observed through six hyperfine transitions around 73.4 GHz.\\	+	A molecular line survey of the prestellar core L1544 between 71.74 and 115.87 GHz was carried out with the IRAM 30 m telescope. Methyleneamidogen was observed through six hyperfine transitions around 73.4 GHz.\\


Line 23:		Line 23:
	----		----

-	Contributor(s): H. S. P. Müller; 12, 2017; 11, 2020	+	Contributor(s): H. S. P. Müller; 09, 2021; 10, 2021

	----		----

h2cnh

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:10:28 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on the Detection of Methanimine in the ISM =====
	+
	+	Methanimine, H<sub>2</sub>CNH, had been identified first in spectra recorded toward Sgr B2 by\\
	+	P. D. Godfrey, R. D. Brown, B. J. Robinson, and M. W. Sinclair,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1973ApL....13..119G\|Discovery of Interstellar Methanimine (Formaldimine)]]\\
	+	//Astrophys. Lett.// 13, 119–121 (1973).\\
	+	Even though only one transition, 1<sub>10</sub> –1<sub>11</sub> near 5290 MHz, was observed the detectionwas quite secure because of the <sup>14</sup>N hyperfine pattern.
	+
	+	Methanimine turned out to be an abundant molecule not only in Sgr B2, but also in other hot core sources; e.g.:\\
	+	J. E. Dickens, W. M. Irvine, C. H. De Vries, and M. Ohishi,\\
	+	[[https://doi.org/10.1086/303884\|Hydrogenation of Interstellar Molecules: A Survey for Methylenimine (CH<sub>2</sub>NH)]]\\
	+	//Astrophys. J.// 479, 307–312 (1997).\\
	+
	+
	+	It was seen in absorption toward the dark cloud L183 and in emission in one of three translucent clouds (CB 17):\\
	+	B. E. Turner, R. Terzieva, and E. Herbst,\\
	+	[[https://doi.org/10.1086/307300\|The Physics and Chemistry of Small Translucent Molecular Clouds. XII. More Complex Species Explainable by Gas-Phase Processes]]\\
	+	//Astrophys. J.// 518, 699–732 (1999).
	+
	+	The detection of the <sup>13</sup>C isotopic species was reported in:\\
	+	S.E. Cummins, R.A. Linke, and P. Thaddeus,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1986ApJS...60..819C\|A Survey of the Millimeter-Wave Spectrum of Sagittarius B2]]\\
	+	//Astrophys. J. Suppl. Ser.// 60, 819–878 (1986).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2006; 03, 2012
	+
	+	----
	+

h2co

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:05:16 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Formaldehyde in Space =====
	+
	+	L. E. Snyder, D. Buhl, B. Zuckerman, and P. Palmer\\
	+	reported on the\\
	+	[[https://doi.org/10.1103/PhysRevLett.22.679\|Microwave Detection of Interstellar Formaldehyde]]\\
	+	//Phys. Rev. Lett.// 22, 679–681 (1969).\\
	+	The 1<sub>1,0</sub> – 1<sub>1,1</sub> transition near 4830 MHz was detected in absorption with the 43 m NRAO telescope toward numerous continuum sources: M17, W3, W3(OH), W49, NGC 2024, DR 21, W43, W44, W51, Sgr A, Sgr B2, W33, NGC 6334, Cas A, and 3C 123. Formaldehyde was only the third poly-atomic molecule detected in space, the fourth molecule by radio astronomy, and the seventh molecule in space.
	+
	+	P. Palmer, B. Zuckerman, D. Buhl, and L. E. Snyder\\
	+	studied\\
	+	[[https://ui.adsabs.harvard.edu/abs/1969ApJ...156L.147P\|Formaldehyde Absorption in Dark Nebulae]]\\
	+	//Astrophys. J.// 156, L147–L150 (1969).\\
	+	The same transition was detected in several positions of Heiles' Cloud 2 with <sup>1</sup>H hyperfine structure resolved in part.
	+
	+	A. Heithausen, U. Mebold, and H. W. de Vries\\
	+	performed\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...179..263H\|A Survey of Formaldehyde in High Galactic Latitudes]]\\
	+	//Astron. Astrophys.// 179, 263–267 (1987),\\
	+	with the Effelsberg 100 m telescope which led to the detection of H<sub>2</sub>CO in translucent clouds.
	+
	+	A. G. Nash\\
	+	studied\\
	+	[[https://ui.adsabs.harvard.edu/abs/1990ApJS...72..303N\|The abundance ratio of formaldehyde to ammonia in molecular clouds observed toward radio continuum sources]]\\
	+	//Astrophys. J. Suppl. Ser.// 72, 303–322 (1990),\\
	+	which led to the detection of H<sub>2</sub>CO in diffuse clouds. The Effelsberg 100 m telescope and the 43 m NRAO dish were employed.
	+
	+	J. Cernicharo, M. Guélin, J. Penalver, J. Martín-Pintado, and R. Mauersberger\\
	+	identified\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989A%26A...222L...1C\|A 200 km/s molecular outflow in the protoplanetary nebula CRL 618]]\\
	+	//Astron. Astrophys.// 222, L1–L4 (1989)\\
	+	in the course of a 3 and 1.3 mm line survey using the IRAM 30 m telescope. The C-rich PPN is also known as V353 Aur.
	+
	+	M. Lindqvist, H. Olofsson, A. Winnberg, and L.-Å. Nyman\\
	+	investigated\\
	+	[[https://ui.adsabs.harvard.edu/abs/1992A%26A...263..183L\|Carbon-bearing molecules in the envelopes around oxygen-rich stars – First detection of formaldehyde in an oxygen-rich circumstellar envelope]]\\
	+	//Astron. Astrophys.// 263, 183–189 (1992).\\
	+	The O-rich CSE was that of the PPN QX Pup, also known as OH231.8+4.2.
	+
	+	K. E. S. Ford, D. A. Neufeld, P. Schilke, and G. J. Melnick\\
	+	reported on the\\
	+	[[https://doi.org/10.1086/423886\|Detection of Formaldehyde toward the Extreme Carbon Star IRC+10216]]\\
	+	//Astrophys. J.// 614, 990–1006 (2004).\\
	+	The source, also known as CW Leo, is an asymptotic giant branch (AGB) star, which is the evolutionary phase prior to the PPN and PN phases.
	+
	+	L. Velilla Prieto, C. Sánchez Contreras, J. Cernicharo, M. Agúndez, G. Quintana-Lacaci, V. Bujarrabal, J. Alcolea, C. Balanca, F. Herpin, K. M. Menten, and F. Wyrowski\\
	+	mentioned the detection of H<sub>2</sub>CO in the envelope of an O-rich AGB star in\\
	+	[[https://doi.org/10.1051/0004-6361/201628776\|The millimeter IRAM-30 m line survey toward IK Tauri]]\\
	+	//Astron. Astrophys.// 597, Art. No. A25 (2017).
	+
	+	Maser activity in formaldehyde was found by\\
	+	D. Downes, T. L. Wilson\\
	+	in their work on\\
	+	[[https://ui.adsabs.harvard.edu/abs/1974ApJ...191L..77D\|Formaldehyde Line Emission at 4.8 GHz near NGC 7538]]\\
	+	//Astrophys. J.// 614, L77–L78 (1974)\\
	+	employing the Effelsberg 100 m telescope.
	+
	+	B. Zuckerman, P. Palmer, L. E. Snyder, and D. Buhl\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1969ApJ...157L.167Z\|Detection of Interstellar H<sub>2</sub><sup>13</sup>C<sup>16</sup>O]]\\
	+	//Astrophys. J.// 157, L167–L171 (1969)\\
	+	in Sgr B2, Sgr A, and possibly W51 using the NRAO 43 m telecope.
	+
	+	F. F. Gardner, J. C. Ribes, and B. F. C. Cooper\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1971ApL.....9..181G\|Detection of the <sup>18</sup>O Isotop(ologu)e of Formaldehyde at 4388 MHz]]\\
	+	//Astrophys. Lett.// 157, 181–183 (1971)\\
	+	in Sgr B2 using the Parkes 64 m telescope.
	+
	+	W. D. Langer, M. A. Frerking, R. A. Linke, and R. W. Wilson, reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1979ApJ...232L.169L\|Detection of Deuterated Formaldehyde in Interstellar Clouds]]\\
	+	//Astrophys. J.// 157, L167–L171 (1969).\\
	+	The Bell Lab. 7 m telescope was used to detect the 2<sub>0,2</sub> – 1<sub>0,1</sub> transition near 128813 MHz in emission toward the dark clouds L134 N and Heiles' Cloud 2.
	+
	+	B. E. Turner\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1990ApJ...362L..29T\|Detection of doubly deuterated interstellar formaldehyde (D<sub>2</sub>CO) – an indicator of active grain surface chemistry]]\\
	+	//Astrophys. J.// 362, L29–L33 (1990).\\
	+	Four transition were detected in emission in the Compact Ridge of Orion KL using the NRAO 12 m telescope.
	+
	+	M. V. Persson, J. K. Jørgensen, H. S. P. Müller, A. Coutens, E. F. van Dishoeck, V. Taquet, H. Calcutt, M. H. D. van der Wiel, T. L. Bourke, and S. F. Wampfler\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201731684\|The ALMA-PILS Survey: Formaldehyde Deuteration in Warm Gas on Small Scales toward IRAS 16293–2422 B]]\\
	+	//Astron. Astrophys.// 610, Art. No. A54 (2018).\\
	+	They identified unambiguously H<sub>2</sub>C<sup>17</sup>O and D<sub>2</sub><sup>13</sup>CO; lines of HD<sup>13</sup>CO were too weak in that frequency range to be detected.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 01, 2017; 03, 2018
	+
	+	----
	+

h2co3

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Aug 2023 10:37:50 +0000

2023/08/24 12:31		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/1538-4357/ace523\|Discovery of the Elusive Carbonic Acid (HOCOOH) in Space]],\\		[[https://doi.org/10.3847/1538-4357/ace523\|Discovery of the Elusive Carbonic Acid (HOCOOH) in Space]],\\
	//Astrophys. J.// 954, Art. No. 3 (2023)\\		//Astrophys. J.// 954, Art. No. 3 (2023)\\
-	The molecule was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m radio telecope. Five lines have good signal-to-noise ratios (S/N) and are unblended or only slightly blended. Some additional ones are more blended or have a less favorable S/N, but strengthen the detection somewhat. As an oblate rotor fairly close to the symmetric limit, the lines frequently consist of quartets of //b//- and //a//-type transitions having the same //J// and //K<sub>c</sub>//. The detected //cis//-//trans// conformer is slightly higher in energy than the //cis//-//cis// conformer, however, this latter conformer has a much lower dipole moment. //Cis//-//trans// carbonic acid is about a factor of ~6.5 and ~31 less abundant than acetic and formic acid, respectively. The //cis//-//cis// conformer may reduce these factors by a factor of around 1.5, possibly more.\\	+	The molecule was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopse. The transitions cover 40 to 111 GHz with 2 ≤ //J// ≤ 9 and //K<sub>a</sub>// ≤ 4. Five lines have good signal-to-noise ratios (S/N) and are unblended or only slightly blended. Some additional ones are more blended or have a less favorable S/N, but strengthen the detection somewhat. As an oblate rotor fairly close to the symmetric limit, the lines frequently consist of quartets of //b//- and //a//-type transitions having the same //J// and //K<sub>c</sub>//. The detected //cis//-//trans// conformer is slightly higher in energy than the //cis//-//cis// conformer, however, this latter conformer has a much lower dipole moment. //Cis//-//trans// carbonic acid is about a factor of ~6.5 and ~31 less abundant than acetic and formic acid, respectively. The //cis//-//cis// conformer may reduce these factors by a factor of around 1.5, possibly more.\\
	\\		\\

h2cs

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:06:32 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Thioformaldehyde in Space =====
	+
	+	After reported unsuccessful searches for the 1<sub>1,0</sub> – 1<sub>1,1</sub> transition of thioformaldehyde, H<sub>2</sub>CS, at 1046.5 MHz, the next higher 2<sub>1,1</sub> – 2<sub>1,2</sub> transition at 3139.4 MHz was detected with the Parkes 64 m radio telescope in absorption toward the Galactic hot core source Sgr B2 by\\
	+	M. W. Sinclair, N. Fourikis, J. C. Ribes, B. J. Robinson, R. D. Brown, and P. D. Godfrey,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1973AuJPh..26...85S\|Detection of Interstellar Thioformaldehyde]]\\
	+	//Aust. J. Phys.// 26, 85–91 (1973).\\
	+
	+
	+	Soon thereafter, the 4<sub>1,3</sub> – 4<sub>1,4</sub> transition was observed with the ARO 46 m telescope by\\
	+	L. H. Doherty, J. M. MacLeod, and T. Oka,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1974ApJ...192L.157D\|Detection of the 10.464 GHz Transition of Interstellar Thioformaldehyde]]\\
	+	//Astrophys. J.// 192, L157–L160 (1974).\\
	+	The line was also seen in absorption toward Sgr B2. The excitation conditions seem to be non-thermal, similar to those of of formaldehyde, H<sub>2</sub>CO.\\
	+	The first two authors also report the detection of the //J// = 3 transition in\\
	+	//BAAS// 7, 265 (1975).\\
	+
	+
	+	The first //R//-branch transition, 3<sub>1,2</sub> – 2<sub>1,1</sub> near 104.617 GHz was detected in emission toward several hot core sources with the NRAO 11 m telecope by\\
	+	H. S. Liszt,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1978ApJ...219..454L\|Upper limits on the abundance of the sulfur dimer in molecular clouds]]\\
	+	//Astrophys. J.// 146, 303–306 (1978).
	+
	+	The 3<sub>1,3</sub> – 2<sub>1,2</sub> transition near 101.478 GHz was also detected toward the cold dense molecular clouds TMC-1 and L134N with the NRAO 43 m telescope by\\
	+	W. M. Irvine, P. Friberg, N. Kaifu, K. Kawaguchi, Y. Kitamura, H. E. Matthews, Y. Minh, S. Saito, N. Ukita, S. Yamamoto,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989ApJ...342..871I\|Observations of some oxygen-containing and sulfur-containing organic molecules in cold dark clouds]]\\
	+	//Astrophys. J.// 342, 871–875 (1989).
	+
	+	Quite recently, H<sub>2</sub>CS was among several molecules detected with the IRAM 30 m telecope in the circumstellar envelope of the carbon-rich AGB star CW Leo, aka IRC +10216:\\
	+	M. Agúndez, J. P. Fonfría Expósito, J. Cernicharo, J. R. Pardo and M. Guélin,\\
	+	[[https://doi.org/10.1051/0004-6361:20078956\|Detection of Circumstellar CH<sub>2</sub>CHCN, CH<sub>2</sub>CN, CH<sub>3</sub>CCH, and H<sub>2</sub>CS]]\\
	+	//Astron. Astrophys.// 479, 493–501 (2008).
	+
	+	The 3<sub>1,3</sub> – 2<sub>1,2</sub> transition of H<sub>2</sub>C<sup>34</sup>S near 99.774 GHz was observed in emission toward Orion KL with the OSO 20 m telescopy by\\
	+	F. F. Gardner, B. Höglund, C. Shurke, A. Stark, and T. L. Wilson,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1985A%26A...146..303G\|Observations of //ortho//- and //para//-thioformaldehyde]]\\
	+	//Astron. Astrophys.// 219, 454–457 (1985).\\
	+
	+
	+	H<sub>2</sub><sup>13</sup>CS was first detected by\\
	+	S. E. Cummins, R. A. Linke, and P. Thaddeus,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1986ApJS...60..819C\|A survey of the millimeter-wave spectrum of Sagittarius B2]]\\
	+	//Astrophys. J.// 576, 819–878 (1986).
	+
	+	The 1<sub>0,1</sub> – 0<sub>0,0</sub> and 3<sub>0,3</sub> – 2<sub>0,2</sub> transitions of HDCS near 31.002 and 92.982 GHz were identified in the course of a Nobeyama 45 m line survey of TMC-1 by\\
	+	H. Minowa, M. Satake, T. Hirota, S. Yamamoto, M. Ohishi, and N. Kaifu,\\
	+	[[https://doi.org/10.1086/311052\|Laboratory Microwave Spectroscopy of HDCS and Its Astronomical Detection toward TMC-1]]\\
	+	//Astrophys. J.// 491, L63–L66 (1997).
	+
	+	Even D<sub>2</sub>CS has been observed with the IRAM 30 m telescopy by\\
	+	N. Marcelino, J. Cernicharo, E. Roueff, M. Gerin, and R. Mauersberger,\\
	+	[[https://doi.org/10.1086/426934\|Deuterated Thioformaldehyde in the Barnard 1 Cloud]]\\
	+	//Astrophys. J.// 620, 308–320 (2005).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 07, 2011
	+
	+	----
	+

h2nc

anonymous@undisclosed.example.com (Anonymous) — Fri, 09 Jun 2023 09:02:25 +0000

2022/03/08 15:43		current
Line 3:		Line 3:
	C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, S. Cuadrado, and J. Cernicharo\\		C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, S. Cuadrado, and J. Cernicharo\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1051/0004-6361/202141491\|Interstellar Detection of the Simplest Aminocarbyne H<sub>2</sub>NC: An ignored but Abundant Molecule, ]]\\	+	[[https://doi.org/10.1051/0004-6361/202141491\|Interstellar Detection of the Simplest Aminocarbyne H<sub>2</sub>NC: An ignored but Abundant Molecule]]\\
	//Astron. Astrophys.// 654, Art. No. A45 (2021).\\		//Astron. Astrophys.// 654, Art. No. A45 (2021).\\
	The aminomethylidyne isomer was observed in the course of molecular line surveys of L483 and B1-b protostellar objects carried out at 3 mm using the IRAM 30 m telescope. The molecule was not detected in corresponding data of the prestellar core TMC-1. The column densities of H<sub>2</sub>CN and H<sub>2</sub>NC were essentially the same in the first two sources.\\		The aminomethylidyne isomer was observed in the course of molecular line surveys of L483 and B1-b protostellar objects carried out at 3 mm using the IRAM 30 m telescope. The molecule was not detected in corresponding data of the prestellar core TMC-1. The column densities of H<sub>2</sub>CN and H<sub>2</sub>NC were essentially the same in the first two sources.\\
		+	\\
		+
		+	D. San Andrés, L. Colzi, V. M. Rivilla, J. García de la Concepción, M. Melosso, J. Martín-Pintado, I. Jiménez-Serra, S. Zeng, S. Martín, M. A. Requena-Torres\\
		+	reported on the\\
		+	[[https://doi.org/10.1093/mnras/stad1385\|H<sub>2</sub>CN/H<sub>2</sub>NC Abundance Ratio: A New Potential Temperature Tracer for the Interstellar Medium]]\\
		+	//Mon. Not. R. Astron. Soc.// 523, 3239–3250 (2023).\\
		+	The authors detect two transitions toward this kinetically warmer source and concomitantly a H<sub>2</sub>CN/H<sub>2</sub>NC ratio of about 2, different from ~1 in the kinetically colder sources L483 and B1-b.\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller; 10, 2021	+	Contributor(s): H. S. P. Müller; 10, 2021; 06, 2023

	----		----

h2nco-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:20:47 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of N-protonated Isocyanic Acid, H2NCO+, in Space =====
	+
	+	Two absorption features in the archival PRIMOS survey of Sagittarius B2(N) were assigned somewhat tentatively to the N-protonated isocyanic acid, H<sub>2</sub>NCO<sup>+</sup>, by\\
	+	H. Gupta, C. A. Gottlieb, V. Lattanzi, J. C. Pearson, and M. C. McCarthy,\\
	+	[[https://doi.org/10.1088/2041-8205/778/1/L1\|Laboratory Measurements and Tentative Astronomical Identification of H<sub>2</sub>NCO<sup>+</sup>]],\\
	+	//Astrophys. J.// 778, L1 (2013).\\
	+	The transitions are 1<sub>01</sub> – 0<sub>00</sub> (//para//) and 2<sub>11</sub> – 1<sub>10</sub> (//ortho//) near 20228 and 40783 GHz, respectively. The amount of spectral lines in that frequency range, in particular those in absorption, are rather small. Moreover, the features show some additional structure caused by <sup>14</sup>N hyperfine structure. Therefore, the identifications is probably quite secure. The rotational temperature was estimated to be close to CMB (2.725 K), possibly slightly higher. This is in accord with the molecule to reside in the not so dense halo of Sgr B2(N) with //n//(H<sub>2</sub>) < 10<sup>4</sup> cm<sup>–3</sup>.
	+
	+	N. Marcelino, M. Agúndez, J. Cernicharo, E. Roueff, and M. Tafalla\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201833074\|Discovery of the Elusive Radical NCO and Confirmation of H<sub>2</sub>NCO<sup>+</sup> in Space]]\\
	+	//Astron. Astrophys.// 612, Art. No. L10 (2018).\\
	+	The cation was detected in the course of a 3 mm line survey of the dense core L483 carried out with the IRAM 30 m telescope. Six //a//-type transitions with //K<sub>a</sub>// = 0 and 1 and //J// = 4 – 3 and 5 – 4 were observed with reasonable to good quality. The cation is about a factor of 400 less abundant in this source than HNCO.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 11, 2013; 05, 2018
	+
	+	----
	+

h2o-plus

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:39:44 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Oxidaniumyl, H2O+, in the Interstellar Medium =====
	+
	+	The //J// = 1.5 – 0.5 fine structure component of the 1<sub>11</sub> –0<sub>00</sub> transition of //ortho//-oxidaniumyl, //o//-H<sub>2</sub>O<sup>+</sup>, near 1115 GHz has recently been detected in absorption with the //Herschel// satellite toward the star-forming regions DR21, Sagittarius B2(M), and NGC 6334:\\
	+	V. Ossenkopf, H. S. P. Müller, D. C. Lis, et al.\\
	+	[[https://doi.org/10.1051/0004-6361/201014577\|Detection of Interstellar Oxidaniumyl: Abundant H<sub>2</sub>O<sup>+</sup> towards the Star-forming Regions DR21, Sgr B2, and NGC6334]]\\
	+	//Astron. Astrophys.// 518, (2010) Art. No. L111.\\
	+	While the spectra toward DR21 and NGC 6334 show partially resolved hyperfine structure, the spectrum toward Sgr B2(M) is rather complex because of additional absorption features caused by diffuse spiral arm clouds.
	+
	+	It is worthwhile mentioning that the same line was also observed in absorption toward several other sources. e.g. toward W31C (G10.6–0.4):\\
	+	M. Gerin, M. De Luca, J. Black, et al.\\
	+	[[https://doi.org/10.1051/0004-6361/201014576\|Interstellar OH<sup>+</sup>, H<sub>2</sub>O<sup>+</sup> and H<sub>3</sub>O<sup>+</sup> along the Sight-line to G10.6–0.4]]\\
	+	//Astron. Astrophys.// 518, (2010) Art. No. L110.\\
	+	This article presents also model calculation which indicate that in these sources OH<sup>+</sup> and H<sub>2</sub>O<sup>+</sup> are formed in the mostly atomic diffuse ISM.
	+
	+	All four fine structure components of the 1<sub>10</sub> – 1<sub>01</sub> transition above 600 GHz have been detected in absorption with the //Herschel// satellite toward Sgr B2(M):\\
	+	P. Schilke, C. Comito, H. S. P. Müller, et al.,\\
	+	[[https://doi.org/10.1051/0004-6361/201015087\|Herschel Observations of //ortho//- and //para//-Oxidaniumyl (H<sub>2</sub>O<sup>+</sup>) in Spiral Arm Clouds toward Sagittarius B2(M)]]\\
	+	//Astron. Astrophys.// 521, (2010) Art. No. L11.\\
	+	The authors investigated the //ortho//-to-//para// ratio of the radical cation.\\
	+	Considering these as well as additional data, including observations of the 1<sub>10</sub> – 1<sub>01</sub> transition around 1630 GHz,\\
	+	P. Schilke, D. C. Lis, E. A. Bergin, R. Higgins, and C. Comito\\
	+	reported on the\\
	+	[[https://doi.org/10.1021/jp312364c\|//Ortho/////Para// Ratio of H<sub>2</sub>O<sup>+</sup> Toward Sagittarius B2(M) Revisited]]\\
	+	//J. Phys. Chem. A// 117, (2013) 9766.\\
	+	The derived values are now all compatible with the high temperature ratio of 3.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 07, 2010; 12, 2013
	+
	+	----
	+

h2o

anonymous@undisclosed.example.com (Anonymous) — Fri, 22 Mar 2024 12:53:10 +0000

2024/03/22 13:40		current
Line 61:		Line 61:
	\\		\\

		+	A. Baudry, K. T. Wong, S. Etoka, A. M. S. Richards, H. S. P. Müller, F. Herpin, T. Danilovich, M. D. Gray, S. Wallström, D. Gobrecht, T. Khouri, L. Decin, C. A. Gottlieb, K. M. Menten, W. Homan, T. J. Millar, M. Montargès, B. Pimpanuwat, J. M. C. Plane, and P. Kervella\\
		+	detected in their investigation\\
		+	[[https://doi.org/10.1051/0004-6361/202245193\|ATOMIUM: Probing the inner wind of evolved O-rich stars with new, highly excited H<sub>2</sub>O and OH lines]]\\
		+	//Astron. Astrophys.// 674, Art. No. A125 (2023)\\
		+	10 highly rotationally or vibrationally excited lines of H<sub>2</sub>O, of which 9 are new detections. The lines were obtained in selected ranges in the frequency region betweeb 222 and 269 GHz. Three of the lines involve the second triad, consisting of the states //v//<sub>2</sub> = //v//<sub>3</sub> = 1, //v//<sub>1</sub> = //v//<sub>2</sub> = 1, and //v//<sub>2</sub> = 3.\\
		+	\\

	----		----

h2o2

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:09:47 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Hydrogen Peroxide, H2O2, in the ISM =====
	+
	+	Six rotational transitions of hydrogen peroxide, H<sub>2</sub>O<sub>2</sub>, were searched for with the APEX 12 m radio telescope toward //ρ// Oph A by\\
	+	P. Bergman, B. Parise, R. Liseau, B. Larsson, H. Olofsson, K. M. Menten, and R. Güsten,\\
	+	[[https://doi.org/10.1051/0004-6361/201117170\|Detection of Interstellar Hydrogen Peroxide]]\\
	+	//Astron. Astrophys.// 531, Art. No. L8 (2011).\\
	+	The //J<sub>K<sub>a</sub>,K<sub>c</sub></sub>// = 3<sub>0,3</sub> – 2<sub>1,1</sub> and 5<sub>0,5</sub> – 4<sub>1,3</sub> of the //τ// = 4 – 2 ladder near 219.2 and 318.2 GHz, respectively, as well as the 6<sub>1,5</sub> – 5<sub>0,5</sub> and 4<sub>0,4</sub> – 3<sub>1,2</sub> of the //τ// = 2 – 4 ladder near 251.9 and 269.0 GHz, respectively, were detected in emission; albeit the latter one only barely with significance.\\
	+	The non-observation of the 1<sub>1,0</sub> – 0<sub>0,0</sub>, //τ// = 3 – 1 transition near 670.6 GHz was attributed to subthermal excitation.\\
	+	A column density of 8 (3) × 10<sup>12</sup>cm<sup>–2</sup> and a rotational temperature of 22 ± 3 K were derived. Since the column density of H<sub>2</sub> is rather uncertain, the fractional abundances of H<sub>2</sub>O<sub>2</sub> with respect to H<sub>2</sub> should be viewed with great caution.\\
	+	The number of observed transitions may seem a bit small, but the low rotational temperature and the corresponding small number of lines detected in that source suggest the observation to be rather secure. Moreover, the strongest evidence for molecular oxygen in the ISM stem from observations of this source.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2011
	+
	+	----
	+

h2s

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:30:31 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Hydrogen Sulfide, H2S, in the ISM =====
	+
	+	Hydrogen sulfide has been detected in seven star-forming regions very early as a very abundant molecule via its 1<sub>10</sub> – 1<sub>01</sub> transition in the 2 mm region:\\
	+	P. Thaddeus, M. L. Kutner, A. A. Penzias, R. W. Wilson, and K. B. Jefferts,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1972ApJ...176L..73T\|Interstellar Hydrogen Sulfide]]\\
	+	//Astrophys. J.// 176, L73–L76 (1972).\\
	+	H<sub>2</sub>S was also identified in this transition toward the circumstellar envelope of OH231.8+4.2:\\
	+	N. Ukita, M. Morris,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1983A%26A...121...15U\|Hydrogen Sulfide in a Circumstellar Envelope]]\\
	+	//Astron Astrophys.// 121, 15–18 (1983);\\
	+	and also in certain regions of the cold dark clouds L134N and TMC-1:\\
	+	Y. C. Minh, W. M. Irvine, and L. M. Ziurys,\\
	+	[[https://doi.org/10.1086/185553\|Detection of Interstellar Hydrogen Sulfide in Cold, Dark Clouds]]\\
	+	//Astrophys. J.// 345, L63–L66 (1989).
	+
	+	The same transition was used to identify H<sub>2</sub><sup>34</sup>S toward certain regions in the Orion molecular cloud:\\
	+	Y. C. Minh, W. M. Irvine, D. McGonagle, and L. M. Ziurys,\\
	+	[[https://doi.org/10.1086/169103\|Observations of the H<sub>2</sub>S toward OMC-1]]\\
	+	//Astrophys. J.// 360, 136–141 (1990).
	+
	+	A weak feature near 333 GHz has been identified as the 2<sub>02</sub> – 1<sub>11</sub> of HDS:\\
	+	G. H. Macdonald, A. G. Gibb, R. J. Habing, and T. J. Millar,\\
	+	[[https://doi.org/10.1051/aas:1996249\|A 330–360 GHz Spectral Survey of G 34.3+0.15. I. Data and Physical Analysis]]\\
	+	//Astron Astrophys. Suppl. Ser.// 119, 333–367 (1996).
	+
	+	Even D<sub>2</sub>S was recently detected toward two dense, cold clouds Barnard 1 and NGC 1333 IRAS 4A(DCO<sup>+</sup>), with HDS detected toward several additional sources:\\
	+	C. Vastel, T. G. Phillips, C. Ceccarelli, and J. C. Pearson,\\
	+	[[https://doi.org/10.1086/378261\|First Detection of Doubly Deuterated Hydrogen Sulfide]]\\
	+	//Astrophys. J.// 593, L97–L100 (2003).
	+
	+	HD<sup>34</sup>S was identified in\\
	+	[[https://doi.org/10.1093/mnras/sty462\|The ALMA-PILS Survey: The Sulfur Connection between Protostars and Comets: IRAS 16293â€“2422 B and 67P/Churyumov-Gerasimenko]]\\
	+	//Mon. Not. R. Astron. Soc.// 476, 4949–4964 (2018) by\\
	+	M. N. Drozdovskaya, E. F. van Dishoeck, J. K. Jørgensen, U. Calmonte, M. H. D. van der Wiel, A. Coutens, H. Calcutt, H. S. P. Müller, P. Bjerkeli, M. V. Persson, S. F. Wampfler, and K. Altwegg.\\
	+	Only the 2<sub>02</sub> – 1<sub>11</sub> transition was detected clearly for HD<sup>34</sup>S and HDS at 332255 and 333279 MHz, respectively. Other lines in the survey were too weak to be detected, as expected. An important detail is that the ratio of approximately 20 is close to the terrestrial value.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2008; 08, 2018
	+
	+	----
	+

h3-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Sep 2020 12:11:51 +0000

2020/09/18 14:05		current
Line 51:		Line 51:
	used the GREAT instrument on board the SOFIA aircraft observatory to detect the 1<sub>0,1</sub> – 0<sub>0,0</sub> ground state transition of //para//-H<sub>2</sub>D<sup>+</sup> at 1370.085 GHz in absorption toward IRAS 16293-2422 and to deduce\\		used the GREAT instrument on board the SOFIA aircraft observatory to detect the 1<sub>0,1</sub> – 0<sub>0,0</sub> ground state transition of //para//-H<sub>2</sub>D<sup>+</sup> at 1370.085 GHz in absorption toward IRAS 16293-2422 and to deduce\\
	[[https://doi.org/10.1038/nature13924\|H<sub>2</sub>D<sup>+</sup> observations give an age of at least one million years for a cloud core forming Sun-like stars]]\\		[[https://doi.org/10.1038/nature13924\|H<sub>2</sub>D<sup>+</sup> observations give an age of at least one million years for a cloud core forming Sun-like stars]]\\
-	//Nature// 516, 219–221 (2014).//	+	//Nature// 516, 219–221 (2014).\\
-	See also the [[https://www.mpifr-bonn.mpg.de/pressreleases/2014/11\|MPIfR press release]] (in English; German version also available) or the [[https://portal.uni-koeln.de/universitaet/aktuell/presseinformationen/detail/das-alter-von-stellaren-kinderstuben\|Universität zu Köln press release]] (in German).\\	+	See also the [[https://www.mpifr-bonn.mpg.de/pressreleases/2014/11\|MPIfR press release]] (in English; [[https://www.mpifr-bonn.mpg.de/pressemeldungen/2014/11\|German version]] also available) or the [[https://portal.uni-koeln.de/universitaet/aktuell/presseinformationen/detail/das-alter-von-stellaren-kinderstuben\|Universität zu Köln press release]] (in German).

h3o-plus

anonymous@undisclosed.example.com (Anonymous) — Thu, 05 Feb 2026 12:04:52 +0000

2026/02/05 12:45		current
Line 47:		Line 47:
	//Phil. Trans. R. Soc. A// 370, (2012) 5162.\\		//Phil. Trans. R. Soc. A// 370, (2012) 5162.\\
	Pure inversion transitions of H<sub>3</sub>O<sup>+</sup> with //J// = //K// up to 11 were detected with the HIFI instrument onboard the //Herschel// satellite toward Sagittarius B2(N). Two components were invoked to occur in the envelope of Sgr B2(N), one with a rotational temperature of about 160 K and one with about 520 K.\\		Pure inversion transitions of H<sub>3</sub>O<sup>+</sup> with //J// = //K// up to 11 were detected with the HIFI instrument onboard the //Herschel// satellite toward Sagittarius B2(N). Two components were invoked to occur in the envelope of Sgr B2(N), one with a rotational temperature of about 160 K and one with about 520 K.\\
		+	\\
		+
		+	Hot, metastable hydronium was also observed toward Sgr B2(M) and toward W31C outside the Galactic center by\\
		+	D. C. Lis, P. Schilke, E. A. Bergin, M. Gerin, J. H. Black, C. Comito, M. De Luca, B. Godard, R. Higgins, F. Le Petit, J. C. Pearson, E. W. Pellegrini, T. G. Phillips, and S. Yu\\
		+	[[https://doi.org/10.1088/0004-637X/785/2/135\|Widespread Rotationally Hot Hydronium Ion in the Galactic Interstellar Medium]]\\
		+	//Astrophys. J.// 785, (2014) Art. No. 135.\\
		+	Values of //T//<sub>rot</sub> were (re) determined as 177 ± 54 K and 546 ± 80 K for Sgr B2(M), 172 ± 51 K and 424 ± 48 K for Sgr B2(N), and about 62 K and 360 K for W31C; fewer transitions were detected for this last source and only up to //J// = //K// = 9.\\
	\\		\\

hac

anonymous@undisclosed.example.com (Anonymous) — Sat, 05 Dec 2020 11:39:18 +0000

2019/06/05 13:22		current
Line 16:		Line 16:
	[[https://doi.org/10.1051/0004-6361/201628648\|The ALMA Protostellar Interferometric Line Survey (PILS): First Results from an Unbiased Submillimeter Wavelength Line Survey of the Class 0 Protostellar Binary IRAS 16293–2422 with ALMA]],\\		[[https://doi.org/10.1051/0004-6361/201628648\|The ALMA Protostellar Interferometric Line Survey (PILS): First Results from an Unbiased Submillimeter Wavelength Line Survey of the Class 0 Protostellar Binary IRAS 16293–2422 with ALMA]],\\
	//Astron. Astrophys.// 595, Art. No. A117 (2016).\\		//Astron. Astrophys.// 595, Art. No. A117 (2016).\\
-	The authors report the first unambiguous detection of acetic acid around a low-mass protostar. There were earlier tentative reports.	+	The authors report the first unambiguous detection of acetic acid around a low-mass protostar. There were earlier tentative reports.\\

		+	C. Xue, A. J. Remijan, C. L. Brogan, T. R. Hunter, E. Herbst, and B. A. McGuire\\
		+	reported on\\
		+	[[https://doi.org/10.3847/1538-4357/ab32e0\|ALMA Detection of Vibrationally Excited (//v//<sub>t</sub> = 1, 2) Acetic Acid toward NGC 6334I]],\\
		+	//Astrophys. J.// 882, Art. No. 118 (2019).\\
		+	Unfortunately, the authors do not presen their model for the ground vibrational state.\\

	----		----

-	Contributor(s): H. S. P. Müller; 2002; 06, 2019.	+	Contributor(s): H. S. P. Müller; 2002; 06, 2019; 12, 2020.

	----		----

han

anonymous@undisclosed.example.com (Anonymous) — Wed, 27 Feb 2019 11:26:09 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Hydroxyacetonitrile, HOCH2CN, in the ISM =====
	+
	+	S. Zeng, D. Quénard, I. Jiménez-Serra J. Martín-Pintado, V. M. Rivilla, L. Testi, and R. Martín-Doménech\\
	+	reported on the\\
	+	[[https://doi.org/10.1093/mnrasl/slz002\|First Detection of the Pre-biotic Molecule Glycolonitrile (HOCH<sub>2</sub>CN) in the Interstellar Medium]]\\
	+	//Mon. Not. R. Astron. Soc.// 484, L43–L48 (2019).\\
	+	Glycolonitrile, also known as hydroxyacetonitrile (HAN), is a sibling of aminoacetonitrile, that was detected more than 10 years ago toward Sagittarius B2(N). HAN was detected in archival ALMA data if the solar-type protostar IRAS 16293–2422 B, were previously methyl chloride was detected. Several lines were detected at 3, 2, and 1.3 mm. Excitation temperatures point at two different temperature regimes, a colder component of around 40 K sampled by transitions with low and intermediate upper state energies and a lukewarm component of about 150 K sampled by transitions with intermediate and higher upper state energies. The lukewarm component is typical for the colder parts of the warm and very dense hot corino, whereas the cold component is typical for the less dense and warmer part of the envelope of IRAS 16293–2422. ALMA is not sensitive to the even lesser dense and cold part of the envelope.\\
	+	Queen Mary University of London issued a [[https://www.qmul.ac.uk/media/news/2019/se/astronomers-find-star-material-could-be-building-block-of-life.html\|press release]].
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 01, 2019
	+
	+
	+	----
	+

harnstoff

anonymous@undisclosed.example.com (Anonymous) — Fri, 06 Nov 2020 11:59:10 +0000

2020/11/06 12:54		current
Line 9:		Line 9:
	I. Jiménez-Serra, J. Martín-Pintado, V. M. Rivilla, L. Rodríguez-Almeida, E. R. Alonso Alonso, S. Zeng, E. J. Cocinero, S. Martín, M. Requena-Torres, R. Martín-Domenech, and L. Testi\\		I. Jiménez-Serra, J. Martín-Pintado, V. M. Rivilla, L. Rodríguez-Almeida, E. R. Alonso Alonso, S. Zeng, E. J. Cocinero, S. Martín, M. Requena-Torres, R. Martín-Domenech, and L. Testi\\
	reported on\\		reported on\\
-	[[https://doi.org/10.1089/ast.2019.2125\|Toward the RNA-World in the Interstellar Medium — Detection of Urea and Search of 2-Aminooxazole and Simple Sugars]]\\	+	[[https://doi.org/10.1089/ast.2019.2125\|Toward the RNA-World in the Interstellar Medium − Detection of Urea and Search of 2-Aminooxazole and Simple Sugars]]\\
-	//Astron. Astrophys.// 20, 1048—1066 (2020).\\	+	//Astrobiology// 20, 1048−1066 (2020).\\
		+	The molecule was detected in the course of n unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), with the IRAM 30 m dish at 3 and 2 mm.

hc_no

anonymous@undisclosed.example.com (Anonymous) — Tue, 27 Dec 2022 12:58:07 +0000

2021/12/20 15:27		current
Line 26:		Line 26:
	Survey]]**\\		Survey]]**\\
	//Astron. Astrophys.// 656, Art. No. L21 (2021).\\		//Astron. Astrophys.// 656, Art. No. L21 (2021).\\
-	Propynonyl, HC<sub>3</sub>O, was identified through two rotational transitions with 2 ≤ //J// ≤ 4 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. 7 of the 8 strong hyperfine components of four fine structure components were detected clearly; two HFS components were unresolved. A value of //T//<sub>rot</sub> = 7 K was taken from C<sub>3</sub>O. HC<sub>5</sub>O is the most abundant of the HC<sub>n</sub>O molecules with n ≥ 1. Setting its relative abundance to 100, they obtained for HCO, HC<sub>2</sub>O, HC<sub>3</sub>O, HC<sub>5</sub>O, and HC<sub>7</sub>O the approximate ratios 79 : 55 : 9 : 100 : 46. Only upper limits were derived for HC<sub>4</sub>O and HC<sub>6</sub>O; these were in both cases similar to those of HC<sub>3</sub>O and thus somewhat constraining.\\	+	Propynonyl, HC<sub>3</sub>O, was identified through two rotational transitions with 2 ≤ //J// ≤ 4 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. 7 of the 8 strong hyperfine components of four fine structure components were detected clearly; two HFS components were unresolved. A value of //T//<sub>rot</sub> = 7 K was taken from C<sub>3</sub>O. HC<sub>5</sub>O is the most abundant of the HC<sub>n</sub>O molecules with n ≥ 1. Setting its relative abundance to 100, they obtained for HCO, HC<sub>2</sub>O, HC<sub>3</sub>O, HC<sub>5</sub>O, and HC<sub>7</sub>O the approximate ratios 79 : 55 : 9 : 100 : 46. Only upper limits were derived for HC<sub>4</sub>O and HC<sub>6</sub>O; these were in both cases similar to those of HC<sub>3</sub>O and are thus somewhat constraining.\\
		+	\\

	----		----

hc_ns

anonymous@undisclosed.example.com (Anonymous) — Tue, 10 Dec 2024 15:07:31 +0000

2024/08/14 15:34		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202140642\|TMC-1, the starless core sulfur factory: Discovery of NCS, HCCS, H<sub>2</sub>CCS, H<sub>2</sub>CCCS, and C<sub>4</sub>S and detection of C<sub>5</sub>S]]\\		[[https://doi.org/10.1051/0004-6361/202140642\|TMC-1, the starless core sulfur factory: Discovery of NCS, HCCS, H<sub>2</sub>CCS, H<sub>2</sub>CCCS, and C<sub>4</sub>S and detection of C<sub>5</sub>S]]\\
	//Astron. Astrophys.// 648, Art. No. L3 (2021).\\		//Astron. Astrophys.// 648, Art. No. L3 (2021).\\
-	The ethenthionyl radical, HCCS, was identified through 2 <sup>1</sup>H hyperfine components of the <sup>2</sup>Π<sub>3/2</sub> //J// = 7/2 − 5/2 transition near 41.1 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The column density is slightly lower than that of H<sub>2</sub>CCS and about a factor of ten lower than that of HCS.\\	+	The ethynylsulfanyl radical, HCCS, was identified through 2 <sup>1</sup>H hyperfine components of the <sup>2</sup>Π<sub>3/2</sub> //J// = 7/2 − 5/2 transition near 41.1 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The column density is slightly lower than that of H<sub>2</sub>CCS and about a factor of ten lower than that of HCS.\\
	\\		\\

Line 19:		Line 19:
	[[https://doi.org/10.1051/0004-6361/202451256\|More sulphur in TMC-1: Discovery of the NC<sub>3</sub>S and HC<sub>3</sub>S radicals with the QUIJOTE line survey]]\\		[[https://doi.org/10.1051/0004-6361/202451256\|More sulphur in TMC-1: Discovery of the NC<sub>3</sub>S and HC<sub>3</sub>S radicals with the QUIJOTE line survey]]\\
	//Astron. Astrophys.// 688, Art. No. L13 (2024).\\		//Astron. Astrophys.// 688, Art. No. L13 (2024).\\
-	Propadienethionyl was detected through three consecutive transitions with 13/2 ≤ //J'// ≤ 17/2 between 34.8 and 45.6 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The lines displayed well-resolved Λ-doubling and (reasonably) resolved <sup>1</sup>H hyperfine structure splitting. Some HFS compoents are (essentially) unblended, several slightly or severely. The authors state abundance ratios HCS/HCCS of ~8.1, HCCS/HC<sub>3</sub>S of ~4.5, and HC<sub>3</sub>S/HC<sub>4</sub>S of ~1.6. HC<sub>5</sub>S was evaluated to be near the present sensitivity limit of the survey.\\	+	Propadienethionyl, HC<sub>3</sub>S, was detected through three consecutive transitions with 13/2 ≤ //J'// ≤ 17/2 between 34.8 and 45.6 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The lines displayed well-resolved Λ-doubling and (reasonably) resolved <sup>1</sup>H hyperfine structure splitting. Some HFS compoents are (essentially) unblended, several slightly or severely. The authors state abundance ratios HCS/HCCS of ~8.1, HCCS/HC<sub>3</sub>S of ~4.5, and HC<sub>3</sub>S/HC<sub>4</sub>S of ~1.6. HC<sub>5</sub>S was evaluated to be near the present sensitivity limit of the survey.\\
	\\		\\

hc2chs

anonymous@undisclosed.example.com (Anonymous) — Wed, 30 Jun 2021 14:57:22 +0000

2021/06/30 16:52		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202141297\|The Sulphur Saga in TMC-1: Discovery of HCSCN and HCSCCH]]\\		[[https://doi.org/10.1051/0004-6361/202141297\|The Sulphur Saga in TMC-1: Discovery of HCSCN and HCSCCH]]\\
	//Astron. Astrophys.// 650, Art. No. L14 (2021).\\		//Astron. Astrophys.// 650, Art. No. L14 (2021).\\
-	HC<sub>2</sub>CHS was identified through 7 //a//-type transitions, of which 5 appear to be unblended, having 5 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 2 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 32.8 and 49.2 GHz. A value of //T//<sub>rot</sub> = 5.0 K was assumed, in keeping with cyanothioformaldehyde. The column density of HC<sub>2</sub>CHS is about a factor of 5 lower than that of the isovalent HC<sub>2</sub>CHO, similar to the corresponding factor of 10 between thioformaldehyde and formaldehyde. In addition, the column density of HC<sub>2</sub>CHS is about a factor of 4 lower than that of the isoelectronic HC(S)CN; the latter molecule is unusually abundant in TMC-1.\\	+	HC<sub>2</sub>CHS was identified through 6 //a//-type transitions, of which 5 appear to be unblended, with 5 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 30.1 and 50.4 GHz. A value of //T//<sub>rot</sub> = 5.0 K was assumed, in keeping with cyanothioformaldehyde. The column density of HC<sub>2</sub>CHS is about a factor of 5 lower than that of the isovalent HC<sub>2</sub>CHO, similar to the corresponding factor of 10 between thioformaldehyde and formaldehyde. In addition, the column density of HC<sub>2</sub>CHS is about a factor of 4 lower than that of the isoelectronic HC(S)CN; the latter molecule is unusually abundant in TMC-1.\\

hc2nh

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:37:55 +0000

hc3nh-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 20:01:54 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Protonated Cyanoacetylene, HC3NH+, in Space =====
	+
	+	K. Kawaguchi, Y. Kasai, S.-I. Ishikawa, M. Ohishi, N. Kaifu, and T. Amano\\
	+	reported on\\
	+	[[https://ui.adsabs.harvard.edu/abs/1994ApJ...420L..95K\|Detection of a new Molecular Ion HC<sub>3</sub>NH<sup>+</sup> in TMC-1]],\\
	+	//Astrophys. J.// 420, L95 – L97 (1994).\\
	+	The //J"// = 3 and 4 transitions near 34.6 and 43.3 GHz were detected in emission using the Nobeyama 45 m dish.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 07, 2015
	+
	+	----
	+

hc3o

anonymous@undisclosed.example.com (Anonymous) — Thu, 29 Oct 2020 08:40:50 +0000

2020/10/26 13:29		current
Line 6:		Line 6:
	//Astron Astrophys.// 642, Art. No. L17 (2020).\\		//Astron Astrophys.// 642, Art. No. L17 (2020).\\
	Two transitions, //J"// = 3 and 4 near 35.7 and 44.6 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Subsequently, two additional transitions, //J"// = 9 and 10 near 89.2 and 98.1 GHz, were identified in data from an older IRAM 30 m line survey of TMC-1. Laboratory measurements confirmed the identity of the molecule as ethynyloxomethylium.\\		Two transitions, //J"// = 3 and 4 near 35.7 and 44.6 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Subsequently, two additional transitions, //J"// = 9 and 10 near 89.2 and 98.1 GHz, were identified in data from an older IRAM 30 m line survey of TMC-1. Laboratory measurements confirmed the identity of the molecule as ethynyloxomethylium.\\
		+
		+	The abundance ratio of C<sub>3</sub>O to HC<sub>3</sub>O<sup>+</sup> is ~7, extremely low, whereas astrochemical modeling with protonation of C<sub>3</sub>O as dominant source of HC<sub>3</sub>O<sup>+</sup> yielded a ratio of ~500 at steady state. The abundance ratio of C<sub>3</sub>S to HC<sub>3</sub>S<sup>+</sup> should be even lower because of the larger proton affinity of C<sub>3</sub>S compared to C<sub>3</sub>O. However, HC<sub>3</sub>S<sup>+</sup> was not detected, and the C<sub>3</sub>S to HC<sub>3</sub>S<sup>+</sup> ratio was evaluated to be larger than 25, strongly suggesting that protonation of C<sub>3</sub>O is not an important source of HC<sub>3</sub>O<sup>+</sup> in TMC-1.\\


Line 13:		Line 15:

	----		----
-

hc3s

anonymous@undisclosed.example.com (Anonymous) — Fri, 26 Feb 2021 15:14:06 +0000

2021/02/26 16:06		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202040013\|Space and laboratory discovery of HC<sub>3</sub>S<sup>+</sup>]]\\		[[https://doi.org/10.1051/0004-6361/202040013\|Space and laboratory discovery of HC<sub>3</sub>S<sup>+</sup>]]\\
	//Astron Astrophys.// 646, Art. No. L3 (2021).\\		//Astron Astrophys.// 646, Art. No. L3 (2021).\\
		+	The //J"// = 5 to 8 transitions between 32.8 and 49.2 GHz were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The identity was confirmed through laboratory measurements. The C<sub>3</sub>S to HC<sub>3</sub>S<sup>+</sup> ratio is 65 ± 20, and the HC<sub>3</sub>O<sup>+</sup> to HC<sub>3</sub>S<sup>+</sup> ratio is 1.0 ± 0.5. The C<sub>3</sub>O to C<sub>3</sub>S ratio, in contrast, is ~0.11.
		+
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller 02, 2021
		+
		+	----
		+

hc4nc

anonymous@undisclosed.example.com (Anonymous) — Thu, 08 Oct 2020 13:19:15 +0000

2020/10/08 15:08		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/2041-8213/aba631\|Detection of Interstellar HC<sub>4</sub>NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions]]\\		[[https://doi.org/10.3847/2041-8213/aba631\|Detection of Interstellar HC<sub>4</sub>NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions]]\\
	//Astrophys. J. Lett.// 900, Art. No. L9 (2020).\\		//Astrophys. J. Lett.// 900, Art. No. L9 (2020).\\
-	The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting at the expense of noise levels of about the same level as the individual lines. The analysis was improved by employing a stacking technique. The HC<sub>4</sub>NC to HC<sub>4</sub>CN ratio is about 1 to 200, while the HC<sub>2</sub>NC to HC<sub>2</sub>CN ratio is about 1 to 50.\\	+	The observations were obtained in the course of the line survey GOTHAM (Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules). The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting of the //J// = 8 → 7, 9 → 9, and 10 → 9 transitions near 22.4, 25.2, and 28.0 GHz, respectively, at the expense of noise levels of about the same level as the individual lines. The analysis was improved by employing a stacking technique. The HC<sub>4</sub>NC to HC<sub>4</sub>CN ratio is about 1 to 200, while the HC<sub>2</sub>NC to HC<sub>2</sub>CN ratio is about 1 to 50.\\

	Almost at the same time,\\		Almost at the same time,\\
Line 12:		Line 12:
	[[https://doi.org/10.1051/0004-6361/202039274\|Discovery of HC<sub>4</sub>NC in TMC-1: A study of the isomers of HC<sub>3</sub>N, HC<sub>5</sub>N, and HC<sub>7</sub>N]]\\		[[https://doi.org/10.1051/0004-6361/202039274\|Discovery of HC<sub>4</sub>NC in TMC-1: A study of the isomers of HC<sub>3</sub>N, HC<sub>5</sub>N, and HC<sub>7</sub>N]]\\
	//Astron. Astrophys.// 642, Art. No. L8 (2020).\\		//Astron. Astrophys.// 642, Art. No. L8 (2020).\\
-		+	The observations were obtained with the Yebes 40m radio telescope in the course of a line survey covering 31.0–50.3 GHz and cover //J"// = 11 to 15 of the molecule. The findings are compatible with the ones mentioned above.
-		+

hc5n

anonymous@undisclosed.example.com (Anonymous) — Tue, 31 Jan 2023 12:15:14 +0000

hc7n

anonymous@undisclosed.example.com (Anonymous) — Wed, 12 Aug 2020 10:42:26 +0000

2019/10/24 09:48		current
Line 25:		Line 25:
	[[https://doi.org/10.1093/mnras/stx2972\|Detection of HC<sub>5</sub>N and HC<sub>7</sub>N Isotopologues in TMC-1 with the Green Bank Telescope]]\\		[[https://doi.org/10.1093/mnras/stx2972\|Detection of HC<sub>5</sub>N and HC<sub>7</sub>N Isotopologues in TMC-1 with the Green Bank Telescope]]\\
	//Mon. Not. R. Astron. Soc.// 474, 5068–5075 (2018); by\\		//Mon. Not. R. Astron. Soc.// 474, 5068–5075 (2018); by\\
-	A. M. Burkhardt, E. Herbst, S. V. Kalenskii, M. C. McCarthy, A. J. Remijan, and B. A. McGuire.	+	A. M. Burkhardt, E. Herbst, S. V. Kalenskii, M. C. McCarthy, A. J. Remijan, and B. A. McGuire.\\
		+
		+	J. R. Pardo, C. Bermúdez, C. Cabezas, M. Agúndez, J. D. Gallego, J. P. Fonfría, L. Velilla-Prieto, G. Quintana-Lacaci, B. Tercero, M. Guélin, and J. Cernicharo\\
		+	reported on the\\
		+	[[https://doi.org/10.1051/0004-6361/202038571\|Detection of Vibrationally Excited HC<sub>7</sub>N and HC<sub>9</sub>N in IRC +10216]]\\
		+	//Astron. Astrophys.// 640, Art. No. L13 (2020).\\
		+	The authors carried out an unbiased molecular line survey with the Yebes 40 m dish between 31 and 50 GHz toward the circumstellar envelope of the famous C-rich AGB star CW Leonis. Numerous transitions of HC<sub>7</sub>N in its lowest excited state //v//<sub>15</sub> = 1 were detected despite a rotational temperature of around 25 K. The derived HC<sub>5</sub>N to HC<sub>7</sub>N ratio is extremely low, roughly 2.4. The derived HC<sub>7</sub>N to HC<sub>9</sub>N ratio is still very low, roughly 7.7.\\


	----		----

-	Contributor(s): H. S. P. Müller; 04, 2012; 01, 2018.	+	Contributor(s): H. S. P. Müller; 04, 2012; 01, 2018; 08, 2020.

	----		----

hc7nh-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 25 Mar 2022 10:15:29 +0000

2022/03/25 11:10		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202142972\|Discovery of a new molecular ion, HC<sub>7</sub>NH<sup>+</sup>, in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202142972\|Discovery of a new molecular ion, HC<sub>7</sub>NH<sup>+</sup>, in TMC-1]]\\
	//Astron Astrophys.// 659, Art. No. L8 (2022).\\		//Astron Astrophys.// 659, Art. No. L8 (2022).\\
-	Nine transitions, from //J"// = 28 to 36 between about 32.1 and 41.0 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Quantum-chemical calculations yielded HC<sub>7</sub>NH<sup>+</sup> as the most likely carrier of these lines. The abundance ratio of HC<sub>5</sub>N to HC<sub>5</sub>NH<sup>+</sup> is ~500, very similar to that of HC<sub>3</sub>N to HC<sub>3</sub>NH<sup>+</sup>, which can be seen as additional support for the identification.\\	+	Nine transitions, from //J"// = 28 to 36 between about 32.1 and 41.0 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Quantum-chemical calculations yielded HC<sub>7</sub>NH<sup>+</sup> as the most likely carrier of these lines. The abundance ratio of HC<sub>7</sub>N to HC<sub>7</sub>NH<sup>+</sup> is ~350, somewhat higher than those of HC<sub>5</sub>N to HC<sub>5</sub>NH<sup>+</sup> and HC<sub>3</sub>N to HC<sub>3</sub>NH<sup>+</sup>, of ~240 and ~230, respectively, which can be seen as additional support for the identification.\\

hc9n

anonymous@undisclosed.example.com (Anonymous) — Wed, 12 Aug 2020 10:43:37 +0000

2019/10/24 09:55		current
Line 9:		Line 9:
	M. B. Bell, L. W. Avery, J. M. MacLeod, and H. E. Matthews,\\		M. B. Bell, L. W. Avery, J. M. MacLeod, and H. E. Matthews,\\
	[[https://ui.adsabs.harvard.edu/abs/1992ApJ...400..551B\|The Excitation Temperature of HC<sub>9</sub>N in the Circumstellar Envelope of IRC +10216]]\\		[[https://ui.adsabs.harvard.edu/abs/1992ApJ...400..551B\|The Excitation Temperature of HC<sub>9</sub>N in the Circumstellar Envelope of IRC +10216]]\\
-	//Astrophys. J.// 400, 551–555 (1992).	+	//Astrophys. J.// 400, 551–555 (1992).\\

	Truong-Bach, D. Graham, and Nguyen-Q-Rieu,\\		Truong-Bach, D. Graham, and Nguyen-Q-Rieu,\\
	[[https://ui.adsabs.harvard.edu/abs/1993A%26A...277..133T\|HC<sub>9</sub>N from the Envelopes of IRC +10216 and CRL 2688]]\\		[[https://ui.adsabs.harvard.edu/abs/1993A%26A...277..133T\|HC<sub>9</sub>N from the Envelopes of IRC +10216 and CRL 2688]]\\
	//Astron. Astrophys.// 277, 133–138 (1993);\\		//Astron. Astrophys.// 277, 133–138 (1993);\\
-	detected one additional higher-//J// transition toward the former source and the same transition in a protoplanetary nebula.	+	detected one additional higher-//J// transition toward the former source and the same transition in a protoplanetary nebula.\\
		+
		+	J. R. Pardo, C. Bermúdez, C. Cabezas, M. Agúndez, J. D. Gallego, J. P. Fonfría, L. Velilla-Prieto, G. Quintana-Lacaci, B. Tercero, M. Guélin, and J. Cernicharo\\
		+	reported on the\\
		+	[[https://doi.org/10.1051/0004-6361/202038571\|Detection of Vibrationally Excited HC<sub>7</sub>N and HC<sub>9</sub>N in IRC +10216]]\\
		+	//Astron. Astrophys.// 640, Art. No. L13 (2020).\\
		+	The authors carried out an unbiased molecular line survey with the Yebes 40 m dish between 31 and 50 GHz toward the circumstellar envelope of the famous C-rich AGB star CW Leonis. Numerous transitions of HC<sub>9</sub>N in its lowest excited state //v//<sub>19</sub> = 1 were detected despite the low rotational temperature. The lines could be assigned unambiguously although no laboratory data were available for this excited state. The derived HC<sub>5</sub>N to HC<sub>7</sub>N ratio is extremely low, roughly 2.4. The derived HC<sub>7</sub>N to HC<sub>9</sub>N ratio is still very low, roughly 7.7.\\


	----		----

-	Contributor(s): H. S. P. Müller; 02, 2006; 06, 2009.	+	Contributor(s): H. S. P. Müller; 02, 2006; 06, 2009; 08, 2020.

	----		----

hc11n

anonymous@undisclosed.example.com (Anonymous) — Mon, 12 Apr 2021 16:34:10 +0000

2021/04/12 18:26		current
Line 24:		Line 24:
	//J. Mol. Spectrosc.// 72, 172–174 (1978);\\		//J. Mol. Spectrosc.// 72, 172–174 (1978);\\
	which in the end turned out to be in full agreement with the laboratory data and thus to be much better than implied by the earlier purported astronomical identification.		which in the end turned out to be in full agreement with the laboratory data and thus to be much better than implied by the earlier purported astronomical identification.
		+
		+	R. A. Loomis, A. M. Burkhardt, C. N. Shingledecker, S. B. Charnley, M. A. Cordiner, E. Herbst, S. Kalenskii, K. L. K. Lee, E. R. Willis, C. Xue, A. J. Remijan, M. C. McCarthy, and B. A. McGuire\\
		+	reported on the\\
		+	[[https://doi.org/10.1038/s41550-020-01261-4\|An investigation of spectral line stacking techniques and application to the detection of HC<sub>11</sub>N]]\\
		+	//Nat. Astron.// 5, 188 (2021).\\
		+	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. The molecule was indentified through line-stacking with a signal-to-noise ratio of 5, which is probably at the edge and may provoke the question if this is the end of this story.\\

hccn_etc

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:39:50 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	The cyanomethylene radical HCCN was observed with the IRAM 30 m telescope in the outer part of the circumstellar shell of the carbon-rich late-type star CW Leo, also known as IRC +10216, by\\		The cyanomethylene radical HCCN was observed with the IRAM 30 m telescope in the outer part of the circumstellar shell of the carbon-rich late-type star CW Leo, also known as IRC +10216, by\\
	M. Guélin and J. Cernicharo,\\		M. Guélin and J. Cernicharo,\\
-	[[http://cdsads.u-strasbg.fr/abs/1991A%26A...244L..21G\|Astronomical Detection of the HCCN Radical – Toward a New Family of Carbon-Chain Molecules ?]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1991A%26A...244L..21G\|Astronomical Detection of the HCCN Radical – Toward a New Family of Carbon-Chain Molecules ?]]\\
	//Astron. Astrophys.// 244, L21–L24 (1991).\\		//Astron. Astrophys.// 244, L21–L24 (1991).\\
	9 fine structure components of 4 rotational transitions (//N// = 4 – 3 to 7 – 6) between 87 and 154 GHz were not or not significantly blended. A rotational temperature of 12±4 K was derived which was modified slightly to 15±2 K in the letter describing the detection of HC<sub>4</sub>N, see below.\\		9 fine structure components of 4 rotational transitions (//N// = 4 – 3 to 7 – 6) between 87 and 154 GHz were not or not significantly blended. A rotational temperature of 12±4 K was derived which was modified slightly to 15±2 K in the letter describing the detection of HC<sub>4</sub>N, see below.\\
Line 10:		Line 10:
	More recently, the detection of the next member, cyanoethynylmethylene, was also detected with the same instrument in the outer part of the circumstellar shell of CW Leo:\\		More recently, the detection of the next member, cyanoethynylmethylene, was also detected with the same instrument in the outer part of the circumstellar shell of CW Leo:\\
	J. Cernicharo, M. Guélin, and J. R. Pardo,\\		J. Cernicharo, M. Guélin, and J. R. Pardo,\\
-	[[http://dx.doi.org/10.1086/426439\|Detection of the Linear Radical HC<sub>4</sub>N in IRC +10216]]\\	+	[[https://doi.org/10.1086/426439\|Detection of the Linear Radical HC<sub>4</sub>N in IRC +10216]]\\
	//Astrophys. J.// 615, L145–L148 (2004).\\		//Astrophys. J.// 615, L145–L148 (2004).\\
	12 fine structure components of 4 rotational transitions (//N// = 18 – 17 to 21 – 20) between 82 and 97 GHz were detected; 4 lines were partially blended. A rotational temperature of 25±4 K was derived, similar to that of HC<sub>3</sub>N in this source.		12 fine structure components of 4 rotational transitions (//N// = 18 – 17 to 21 – 20) between 82 and 97 GHz were detected; 4 lines were partially blended. A rotational temperature of 25±4 K was derived, similar to that of HC<sub>3</sub>N in this source.
Line 18:		Line 18:

	Contributor(s): H. S. P. Müller; 11, 2004; 01, 2012		Contributor(s): H. S. P. Müller; 11, 2004; 01, 2012
-

	----		----

hccnc

anonymous@undisclosed.example.com (Anonymous) — Tue, 09 Apr 2024 08:31:33 +0000

2024/04/08 16:26		current
Line 43:		Line 43:
	[[https://doi.org/10.1051/0004-6361/202348822\|Study of the HCCNC and HNCCC isotopologs in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202348822\|Study of the HCCNC and HNCCC isotopologs in TMC-1]]\\
	//Astron. Astrophys.// 682, Art. No. L13 (2024).\\		//Astron. Astrophys.// 682, Art. No. L13 (2024).\\
-	They reported in the framework of improved data of the above survey the detection of HCC<sup>15</sup>NC with a <sup>14</sup>N/<sup>15</sup>N ratio of roughly 240, slightly lower than ~317 obtained for HC<sub>3</sub>N. However, this value may be affected by a probable but at that time unrecognized blending of the //J// = 5 − 4 transition of HCC<sup>15</sup>NC (J. Cernicharo, private communication). They also redetermined the <sup>12</sup>C/<sup>13</sup>C ratios. The values are ~95 with scatter that is insignificant with respect to the uncertainties. These values are somewhat lower than ~65 usually found in the the local ISM, but very similar to values of HNC<sub>3</sub> <sup>13</sup>C isotopomers and to two of the three HC<sub>3</sub>N <sup>13</sup>C isotopomers. An H/D ratio of ~ 31 was reported, but it appears again as if the //J// = 5 − 4 transition of DCCNC is too strong. The ratio from 4 − 3 alone would be closer to ~55 observed for HNC<sub>3</sub> and HC<sub>3</sub>N.\\	+	They reported in the framework of improved data of the above survey the detection of HCC<sup>15</sup>NC with a <sup>14</sup>N/<sup>15</sup>N ratio of roughly 240, slightly lower than ~317 obtained for HC<sub>3</sub>N. However, this value may be affected by a probable but at that time unrecognized blending of the //J// = 5 − 4 transition of HCC<sup>15</sup>NC (J. Cernicharo, private communication). They also redetermined the <sup>12</sup>C/<sup>13</sup>C ratios. The values are ~95 with scatter that is insignificant with respect to the uncertainties. These values are somewhat lower than ~65 usually found in the the local ISM, but very similar to values of HNC<sub>3</sub> <sup>13</sup>C isotopomers and to two of the three HC<sub>3</sub>N <sup>13</sup>C isotopomers. An H/D ratio of ~31 was reported, substantially lower than ~55 observed for HNC<sub>3</sub> and HC<sub>3</sub>N.\\
	\\		\\

hccnch

anonymous@undisclosed.example.com (Anonymous) — Fri, 25 Mar 2022 13:45:18 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Protonated Isocyanoacetylene in the ISM =====
	+
	+	M. Agúndez, C. Cabezas, N. Marcelino, R. Fuentetaja, B. Tercero, P. de Vicente, and J. Cernicharo\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/202243396\|A new protonated molecule discovered in TMC-1: HCCNCH<sup>+</sup>]]\\
	+	//Astron Astrophys.// 659, Art. No. L9 (2022).\\
	+	Two transitions, //J"// = 3 and 4 near 37.3 and 46.6 GHz, of a new, unknown molecule were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. Subsequently, two additional transitions, //J"// = 8 and 9 near 84.0 and 93.3 GHz, were identified in data from an older IRAM 30 m line survey of TMC-1. Quantum-chemical calculations supported the assignment to HCCNCH<sup>+</sup>.\\
	+
	+	The abundance ratio of HCCCNC to HCCCNCH<sup>+</sup> is ~10. This extremely low ratio is reproduced well with the reaction of C<sup>+</sup> and CH<sub>3</sub>CN being the main source of HCCNCH<sup>+</sup>.\\
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller 03, 2022
	+
	+	----

hcco

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:10:47 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Ketenyl Radical, HCCO, in the ISM =====
	+
	+	The ketenyl radical is almost linear with the //K<sub>a</sub>// = 1 levels being so high in energy that for astronomical observations it can be treated as being linear.\\
	+	M. Agúndez, J. Cernicharo, and M. Guélin\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201526317\|Discovery of Interstellar Ketenyl (HCCO), a Surprisingly Abundant Radical]]\\
	+	//Astron. Astrophys.// 577, Art. No. L5 (2015).\\
	+	The IRAM 30 m telescope was used to detect the four Δ//F// = Δ//J// = Δ//N// hyperfine components with //N// = 4 – 3 near 86.65 GHz toward the dense core Lupus-1A, which is in the vicinity of the low-mass protostar IRAS 15398-3359, and toward the the young stellar object IRAS 18148–0440 in the L483 dense core.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2015
	+
	+	----
	+

hccs-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 27 Jun 2023 10:58:05 +0000

2022/03/08 15:56		current
Line 1:		Line 1:
	===== On the Detection of Thioketenylium, HCCS<sup>+</sup>, in the ISM =====		===== On the Detection of Thioketenylium, HCCS<sup>+</sup>, in the ISM =====

-	C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, Y. Endo, R. Fuentetaja, J. R. Pardo, P. de Vicente, and J. Cernicharo\\	+	C. Cabezas, M. Agúndez, N. Marcelino, B. Tercero, Y. Endo, R. Fuentetaja, J. R. Pardo, P. de Vicente, and J. Cernicharo\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.1051/0004-6361/202142815\|Discovery of the Elusive Thioketenylium, HCCS<sup>+</sup>, in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202142815\|Discovery of the Elusive Thioketenylium, HCCS<sup>+</sup>, in TMC-1]]\\
	//Astron. Astrophys.// 654, Art. No. A45 (2021).\\		//Astron. Astrophys.// 654, Art. No. A45 (2021).\\
-	Thioketenylium, HCCS<sup>+</sup>, was observed in the course of molecular line surveys of TMC-1 carried out at 7 and 3 mm using the Yebes 40 m and IRAM 30 m telescopes, respectively. Rotational transitions with //N// = 2 − 1 to 4 − 3 and 6 − 5 to 8 − 7 were identified between 32.1 and 99.7 GHz with resolved fine and <sup>1</sup>H hyperfine splitting (not all fine structure components were covered). The column CCS/HCCS<sup>+</sup> column density ratio of 50 ± 10 is similar to those of CS/HCS<sup>+</sup> (35 ± 8) and CCCS/HCCCS<sup>+</sup> (65 ± 20).\\	+	Thioketenylium, HCCS<sup>+</sup>, was observed in the course of molecular line surveys of TMC-1 carried out at 7 and 3 mm using the Yebes 40 m and IRAM 30 m telescopes, respectively. Rotational transitions with //N// = 2 − 1 to 4 − 3 and 6 − 5 to 8 − 7 were identified between 32.1 and 99.7 GHz with resolved fine and <sup>1</sup>H hyperfine splitting (not all fine structure components were covered). The CCS/HCCS<sup>+</sup> column density ratio of 50 ± 10 is similar to those of CS/HCS<sup>+</sup> (35 ± 8) and CCCS/HCCCS<sup>+</sup> (65 ± 20).\\

	----		----

hcl-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:12:40 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Chloroniumyl, HCl+, in the Interstellar Medium =====
	+
	+	The //J// = 5/2 – 3/2 transition of the lower energy fine structure component <sup>2</sup>Π<sub>3/2</sub> of chloroniumyl has been detected in absorption in the diffuse medium along the sight-lines to the submillimeter continuum sources W31C and W49N by\\
	+	M. De Luca, H. Gupta, D. Neufeld, M. Gerin, D. Teyssier, B. J. Drouin, J. C. Pearson, D. C. Lis, R. Monje, T. G. Phillips, J. R. Goicoechea, B. Godard, E. Falgarone, A. Coutens, and T. A. Bell,\\
	+	[[https://doi.org/10.1088/2041-8205/751/2/L37\|//Herschel///HIFI Discovery of HCl<sup>+</sup> in the Interstellar Medium]]\\
	+	//Astrophys. J.// 751, (2012), Art. No. L37.\\
	+	Two structured features, caused by the <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs, were observed near 1444 and 1442 GHz. The intricate structure of the features was caused by various clouds along the sight-line, Λ-doubling, and Cl hyperfine structure. The inferred column densities are very similar to those of H<sub>2</sub>Cl<sup>+</sup> and HCl in these sources.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2012.
	+
	+
	+	----
	+

hcl

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:50:41 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Hydrogen Chloride, HCl, in Space =====
	+
	+	The //J// = 1 – 0 transition of HCl was detected in emission with the KAO:\\
	+	G. A. Blake, J Keene, and T. G. Phillips,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1985ApJ...295..501B\|Chlorine in Dense Interstellar Clouds – The Abundance of HCl in OMC-1]]\\
	+	//Astrophys. J.// 295, 501–506 (1985).\\
	+	More recently, this transition was mapped with the CSO:\\
	+	P. Schilke, T. G. Phillips, and N. Wang,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1995ApJ...441..334S\|Hydrogen Chloride in OMC-1]]\\
	+	//Astrophys. J.// 441, 334–342 (1995).
	+
	+	The Hubble Space Telescope has been used to detect HCl in the diffuse medium toward ζ Oph via its UV spectrum by:\\
	+	S. R. Federman, J. A. Cardell, E. F. van Dishoek, D. L. Lambert, and J. H. Black,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1995ApJ...445..325F\|Vibrationally Excited H<sub>2</sub>, HCl, and NO<sup>+</sup> in the Diffuse Clouds toward ζ Ophiuchi]]\\
	+	//Astrophys. J.// 445, 325–329 (1995).
	+
	+	HCl was also seen with the KAO in absorption toward Sgr B2, just as HF soon thereafter:\\
	+	J. Zmuidzinas, G. A. Blake, J. Carlsstrom, J. Keene, and D. Miller,\\
	+	[[https://doi.org/10.1086/309570\|HCl Absorption Toward Sagittarius B2]]\\
	+	//Astrophys. J.// 447, L125–L128 (1995).
	+
	+	The molecule is also present in the circumstellar envelope of the carbon rich star CW Leo:\\
	+	J. Cernicharo, L. Decin, M. J. Barlow, et al.,\\
	+	[[https://doi.org/10.1051/0004-6361/201014553\|Detection of Anhydrous Hydrochloric Acid, HCl, in IRC +10216 with the //Herschel// SPIRE and PACS spectrometers]]\\
	+	//Astron. Astrophys.// 518, Art. No. L136 (2010).
	+
	+	Several rovibrational transitions of HCl around 2850 cm<sup>–1</sup> or 3.5 μm were detected in absorption with CRIRES at the Very Large Telescope and, more extensively, with IRCS at the Subaru Telescope toward CRL 2136 by:\\
	+	M. Goto, T. Usuda, T. R. Geballe, K. M. Menten, N. Indriolo, and D. A. Neufeld,\\
	+	[[https://doi.org/10.1051/0004-6361/201322225\|Fundamental Vibrational Transitions of Hydrogen Chloride Detected in CRL 2136]]\\
	+	//Astron. Astrophys.// 558, Art. No. L5 (2013).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 03, 2007; 08, 2011; 11, 2013
	+
	+
	+	----
	+

hcn

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:23:32 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on Hydrogen Cyanide in the ISM/CSM Observed by Rotational Spectroscopy =====
	+
	+	HCN is abundant in all kinds of environments, from dark clouds to star-forming regions and circumstellar envelopes. The Detection of Interstellar HCN was reported in detail by\\
	+	L. E. Snyder and D. Buhl,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1971ApJ...163L..47S\|Observations of Radio Emission from Interstellar Hydrogen Cyanide]]\\
	+	//Astrophys. J.// 163, L47–L52 (1971).\\
	+	The detection of H<sup>13</sup>CN was also reported.
	+
	+	Note: Often one finds confusion about the two stretching modes of HCN. According to the generally accepted recommendation, we designate //v//<sub>1</sub> = 1 as the H-C stretching state at 3311.5 cm<sup>–1</sup> or 4764 K, and //v//<sub>3</sub> = 1 as the C-N stretching state at 2096.8 cm<sup>–1</sup> or 3017 K. Rather frequently, the numbering of the two stretching states is exchanged. And on occasion people use the wrong state designations.\\
	+	States are designated according to the number of quanta excited: (//v//<sub>1</sub>//v//<sub>2</sub>//v//<sub>3</sub>).
	+
	+	L. M. Ziurys and B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1986ApJ...300L..19Z\|Detection of Interstellar Vibrationally Excited HCN]]\\
	+	//Astrophys. J.// 300, L19–L23 (1986),\\
	+	reported on the detection of HCN transitions within (010) and (020). Emission lines of both states were seen in the circumstellar envelope of CW Leo, aka IRC +10216. Lines of (010) were also detected toward Orion KL.
	+
	+	T. D. Groesbeck, T. G. Philips, and G. A. Blake,\\
	+	[[https://doi.org/10.1086/192076\|The Molecular Emission-Line Spectrum of IRC +10216 Between 330 and 358 GHz]]\\
	+	//Astrophys. J. Suppl. Ser.// 94, L147–L162 (1994),\\
	+	report on the detection of HCN transitions within (001) and (100) as well as (010) of H<sup>13</sup>CN.
	+
	+	The observation of even higher states, up to (120), was reported by\\
	+	L. W. Avery //et al.//,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1994ApJ...426..737A\|Submillimeter molecular line observations of IRC +10216: Searches for MgH, SiH<sub>2</sub>, and HCO<sup>+</sup>, and detection of hot HCN]]\\
	+	//Astrophys. J.// 426, 737–741 (1994).\\
	+	In this paper, the stretching states are designated as indicated above. However, the authors claimed they were using the traditional labelling.
	+
	+	A plethora of excited vibrational states, several still higher than those described above (up to almost 11000 K), were detected, again toward CW Leo by\\
	+	J. Cernicharo, M. Agúndez, C. Kahane, M. Guélin, J. R. Goicoechea, N. Marcelino, E. De Beck, and L. Decin,\\
	+	[[https://doi.org/10.1051/0004-6361/201116717\|Probing the Dust Formation Region in IRC +10216 with the High Vibrational States of Hydrogen Cyanide]]\\
	+	//Astron. Astrophys.// 529, Art. No. L3 (2011).
	+
	+	Maser emission within (010) and (020) was reported by\\
	+	S. Guilloteau, A. Omont, and R. Lucas,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...176L..24G\|A New Strong Maser – HCN]]\\
	+	//Astron. Astrophys.// 176, L24–L26 (1987); and\\
	+	R. Lucas and J. Cernicharo,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989A%26A...218L..20L\|Discovery of Strong Maser Emission from HCN in IRC+10216]]\\
	+	//Astron. Astrophys.// 218, L20–L22 (1989).
	+
	+	Maser emission involving the Coriolis-coupled (040) and (001) states was reported by\\
	+	P.Schilke, D. M. Mehringer, and K. M. Menten,\\
	+	[[https://doi.org/10.1086/312416\|A Submillimeter HCN Laser in IRC +10216]]\\
	+	//Astrophys. J.// 528, L37–L40 (2000); and\\
	+	P.Schilke, D. M. Mehringer, and K. M. Menten\\
	+	[[https://doi.org/10.1086/345099\|Detection of a Second, Strong Submillimeter HCN Laser Line toward Carbon Stars]]\\
	+	//Astrophys. J.// 583, 446–450 (2003).
	+
	+	The detection of direct-//l//-type transitions (Δ//J// = 0) within (010) paved the way for observing vibrationally excited HCN at centimeter wavelengths !\\
	+	S. Thorwirth, F. Wyrowski, P. Schilke, K. M. Menten, S. Brünken, H. S. P. Müller, and G. Winnewisser,\\
	+	[[https://doi.org/10.1086/367629\|Detection of HCN Direct-//l//-Type Transitions Probing Hot Molecular Gas in the Proto-Planetary Nebula CRL 618]]\\
	+	//Astrophys. J.// 586, 338–343 (2003).
	+
	+	Early observations of DCN were reported by\\
	+	K. B. Jefferts, A. A.Penzias, and R. W. Wilson,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1973ApJ...179L..57J\|Deuterium in the Orion Nebula]]\\
	+	//Astrophys. J.// 179, L57–L59 (1973); and by\\
	+	R. W. Wilson, A. A.Penzias, K. B. Jefferts, and P. M. Solomon,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1973ApJ...179L.107W\|Interstellar Deuterium: the Hyperfine Structure of DCN]]\\
	+	//Astrophys. J.// 179, L107–L110 (1973).\\
	+	More recently, DCN was observed even in the photodissociation region Orion Bar:\\
	+	S. Leurini, R. Rolffs, S. Thorwirth, B. Parise, P. Schilke, C. Comito, F. Wyrowski, R. Güsten, P. Bergman, K. M. Menten and L.-Å. Nyman,\\
	+	[[https://doi.org/10.1051/0004-6361:20065555\|APEX 1 mm Line Survey of the Orion Bar]]\\
	+	//Astron. Astrophys.// 454, L47–L50 (2006).
	+
	+	Early observations of HC<sup>15</sup>N were reported by\\
	+	R. A. Linke, P. F. Goldsmith, P. G. Wannier, R. W. Wilson, and A. A.Penzias,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1977ApJ...214...50L\|Isotopic Abundance Variations in Interstellar HCN]]\\
	+	//Astrophys. J.// 214, 50–59 (1977).
	+
	+	Transitions pertaining to (010) of H<sup>13</sup>CN had been seen earlier, see above; transitions up to (030) were reported by\\
	+	J. Cernicharo, M. Agúndez, C. Kahane, M. Guélin, J. R. Goicoechea, N. Marcelino, E. De Beck, and L. Decin,\\
	+	[[https://doi.org/10.1051/0004-6361/201116717\|Probing the Dust Formation Region in IRC +10216 with the High Vibrational States of Hydrogen Cyanide]]\\
	+	//Astron. Astrophys.// 529, Art. No. L3 (2011).
	+
	+	Rovibrational transitions have been also detected:\\
	+	S. T. Ridgway, D. F. Carbon, and D. N. B. Hall,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1978ApJ...225..138R\|Polyatomic Species Contributing to the Carbon-star 3 micron Band]]\\
	+	//Astrophys. J.// 225, 138–147 (1978).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 04, 2004; 03, 2007; 06, 2011
	+
	+	----
	+

hcnh-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 28 Oct 2020 10:59:38 +0000

2019/10/22 16:40		current
Line 7:		Line 7:
	The //J"// = 0, 1, and 2 transitions near 74.1, 148.2 and 222.3 GHz were detected in emission toward Sgr B2(OH) using the NRAO 12 m dish for the former, and the Texas MWO 4.9 m dish for the latter two transitions.		The //J"// = 0, 1, and 2 transitions near 74.1, 148.2 and 222.3 GHz were detected in emission toward Sgr B2(OH) using the NRAO 12 m dish for the former, and the Texas MWO 4.9 m dish for the latter two transitions.

-	L. M. Ziurys, A. J. Apponi, and J. T. Yoder\\	+	P. Schilke, C. M. Walmsley, T. J. Millar, and C. Henkel\\
	reported on the\\		reported on the\\
-	[[https://ui.adsabs.harvard.edu/abs/1992ApJ...397L.123Z\|Detection of the Quadrupole Hyperfine Structure in HCNH<sup>+</sup>]],\\	+	[[https://ui.adsabs.harvard.edu/#abs/1991A&A...247..487S/abstract\|Protonated HCN in molecular clouds]],\\
-	//Astrophys. J.// **397, L123 – L126 (1992**).\\	+	//Astron. Astrophys.// **247, 487 – 496 (1991**).\\
-	They detected the ground state transition toward the dark cloud TMC-1 using the NRAO 12 m dish.	+	They detected the //J"// = 1 and 2 transition toward the dark cloud TMC-1 using the IRAM 30 m dish.


	----		----

-	Contributor(s): H. S. P. Müller; 07, 2015	+	Contributor(s): H. S. P. Müller; 07, 2015; 10, 2020

	----		----

hcno

anonymous@undisclosed.example.com (Anonymous) — Thu, 01 Feb 2024 13:22:09 +0000

2024/02/01 14:19		current
Line 54:		Line 54:
	\\		\\

		+	J. Cernicharo, M. Agúndez, C. Cabezas, B. Tercero, R. Fuentetaja, N. Marcelino, and P. de Vicente \\
		+	announced the\\
		+	**[[https://doi.org/10.1051/0004-6361/202349105\|Discovery of thiofulminic acid with the QUIJOTE line survey:
		+	A study of the isomers of HNCS and HNCO in TMC-1]]**\\
		+	//Astron. Astrophys.// 682, (2024), Art. No. L4.\\
		+	The authors detect H<sup>15</sup>NCO about a factor of 330 lower in abundance that the main isotopolog.\\
		+	\\

	----		----
Line 103:		Line 110:
	----		----

-	Contributor(s): H. S. P. Müller; 02, 2009; 05, 2009; 05, 2010; 03, 2012; 06, 2016; 05, 2018; 09, 2019	+	Contributor(s): H. S. P. Müller; 02, 2009; 05, 2009; 05, 2010; 03, 2012; 06, 2016; 05, 2018; 09, 2019; 02, 2024

	----		----

hcns

anonymous@undisclosed.example.com (Anonymous) — Wed, 17 Apr 2024 10:50:23 +0000

2024/02/01 13:55		current
Line 26:		Line 26:
	//Astron. Astrophys.// 575, (2015), Art. No. A84.\\		//Astron. Astrophys.// 575, (2015), Art. No. A84.\\
	The molecules were identified in the course of a line survey of the circumstellar envelope of this O-rich AGB star, aka QX Pup, with the IRAM 30 m dish at 3 to 1 mm.\\		The molecules were identified in the course of a line survey of the circumstellar envelope of this O-rich AGB star, aka QX Pup, with the IRAM 30 m dish at 3 to 1 mm.\\
		+	\\
		+
		+	M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, J. Martín-Pintado, L. Colzi, S. Zeng, A. Megías, Á. López-Gallifa, A. Martínez-Henares, S. Massalkhi, B. Tercero, P. de Vicente, D. San Andrés, S. Martín, and M. A. Requena-Torres\\
		+	announced the\\
		+	[[https://doi.org/10.3847/1538-4357/ad2c01\|Interstellar Detection of O-protonated Carbonyl Sulfide, HOCS<sup>+</sup>]]\\
		+	//Astrophys. J.// 965, Art. No. 149 (2024).\\
		+	The results were obtained in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes. The //K<sub>a</sub>// = 0 lines of HOCS<sup>+</sup> were blended with those of HNC<sup>34</sup>S because of nearly identical values of //B + C//. The transitions cover 34 to 161 GHz with //J"// = 2, 3, 6 − 13. The contribution of HNC<sup>34</sup>S could be accounted for accurately through lines of HNCS, OCS, and OC<sup>34</sup>S and turned out to be less than that of HOCS<sup>+</sup>. Several lines are slightly or more severely blended in addition, but this is in most cases also well accounted.\\
	\\		\\

	----		----

-	Contributor(s): H. S. P. Müller; 09, 2009; 02, 2024	+	Contributor(s): H. S. P. Müller; 09, 2009; 02, 2024; 04, 2024

	----		----

hco-plus

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:26:23 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of HCO+ in the ISM =====
	+
	+	D. Buhl and L. E. Snyder\\
	+	detected an\\
	+	[[https://doi.org/10.1038/228267a0\|Unidentified Interstellar Microwave Line]]\\
	+	//Nature// 228, 267–269 (1970)\\
	+	strongly in emission at 89190 ± 2 MHz toward the high-mass star-forming regions W3(OH), Orion, Sgr A NH<sub>3</sub>A) and W51 and toward the dark cloud L134 using the 11 m NRAO telescope.
	+
	+	W. Klemperer\\
	+	concomitantly suggested the\\
	+	[[https://doi.org/10.1038/2271230a0\|Carrier of the Interstellar 89.190 GHz Line]]\\
	+	//Nature// 227, 1230 (1970)\\
	+	to be the ground state transition of HCO<sup>+</sup> based on structure considerations.
	+
	+	R. C. Woods, T. A. Dixon, R. J. Saykally, and P. G. Szanto\\
	+	proved this suggestion by measuring the\\
	+	[[https://doi.org/10.1103/PhysRevLett.35.1269\|Laboratory Microwave Spectrum of HCO<sup>+</sup>]]\\
	+	//Phys. Rev. Lett.// 35, 1269–1272 (1975)\\
	+	at the frequency derived from radio astronomical observations.
	+
	+	L. E. Snyder, J. M. Hollis, F. J. Lovas, and B. L. Ulich\\
	+	reported slightly later on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1976ApJ...209...67S\|Detection, Identification, and Observations of Interstellar H<sup>13</sup>CO<sup>+</sup>]]\\
	+	//Astrophys. J.// 209, 67–74 (1976)\\
	+	at 86754 MHz, close to the predicted frequencies. The NRAO 11 m telecope was used, and the line was detected in several sources: DR21, DR21(OH), NGC 2264, NGC 7538, Rrion A, Sgr B2(OH), W3(OH), W49, W51, and W75N.
	+
	+	The [[https://ui.adsabs.harvard.edu/abs/1976ApJ...209L..83H\|Radio Detection of Interstellar DCO<sup>+</sup>]]\\
	+	//Astrophys. J.// 209, L83–L85 (1976)\\
	+	with the NRAO 11 m telecope toward DR21(OH), L134, and NGC 2264 was reported by\\
	+	J. M. Hollis, L. E. Snyder, F. J. Lovas, and D. Buhl.
	+
	+	M. Guélin and P. Thaddeus\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1976ApJ...209L..83H\|Detection of HC<sup>18</sup>O<sup>+</sup> in Sagittarius B2]]\\
	+	//Astrophys. J.// 209, L139–L141 (1979)\\
	+	again using the NRAO 11 m telecope.
	+
	+	M. Guélin, W. D. Langer, and R. W. Wilson\\
	+	studied the distribution of 5 isotoplogs of HCO<sup>+</sup> in several sources:\\
	+	[[https://ui.adsabs.harvard.edu/abs/1982A%26A...107..107G\|The State of Ionization in Dense Molecular Clouds]]\\
	+	//Astron. Astrophys.// 107, 107–127 (1982).\\
	+	The observations were performed with the Bell Lab. 7 m telescope. In the course of the investigations, D<sup>13</sup>CO<sup>+</sup> was detected in TMC-1 and in L183.
	+
	+	M. Guélin, J. Cernicharo, and R. A. Linke\\
	+	described the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1982ApJ...263L..89G\|Detection of HC<sup>17</sup>O<sup>+</sup> in Sagittarius&nsp;B2]]\\
	+	//Astrophys. J.// 263, L89–L93 (1982)\\
	+	using the Bell Lab. 7 m telescope.
	+
	+	HCO<sup>+</sup> was also detected in the diffuse medium toward the extragalactic contiunuum sources QSO B0212+735, $C 50.11 (NRAO150), and BL Lac by\\
	+	R. Lucas and H. Liszt,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1982ApJ...263L..89G\|Plateau de Bure Observations of mm-wave Molecular Absorption from <sup>13</sup>CO, HCO<sup>+</sup>, and HCN]]\\
	+	//Astron. Astrophys.// 282, L5–L8 (1994).
	+
	+	L. M. Ziurys, E. D. Tenenbaum, R. L. Pulliam, N. J. Woolf, and S. N. Milam,\\
	+	[[https://doi.org/10.1088/0004-637X/695/2/1604\|Carbon Chemistry in the Envelope of VY Canis Majoris: Implications for Oxygen-Rich Evolved Stars]]\\
	+	//Astrophys. J.// 695, 1604–1613 (2009);\\
	+	detected HCO<sup>+</sup> in the circumstellar envelope of this star using the ARO 12 m dish as well as the ARO SMT.
	+
	+	R. L. Pulliam, J. L. Edwards, and L. M. Ziurys,\\
	+	studied the\\
	+	[[https://doi.org/10.1088/0004-637X/743/1/36\|Circumstellar Ion-Molecule Chemistry: Observations of HCO<sup>+</sup> in the Envelopes of O-rich Stars and IRC+10216]]\\
	+	//Astrophys. J.// 743, Art. No. 36 (2011).\\
	+	CW Leo, also known as IRC+10216, is a carbon-rich AGB star. Again, the ARO 12 m dish as well as the ARO SMT were employed.
	+
	+	J. R. Najita, J. S. Carr, S. E. Strom, D. M. Watson, I. Pascucci, D. Hollenbach, U. Gorti, and L. Keller\\
	+	reported on\\
	+	[[https://doi.org/10.1088/0004-637X/712/1/274\|//Spitzer// Spectroscopy of the Transition Object TW Hya]]\\
	+	//Astrophys. J.// 712, 274–286 (2010).\\
	+	The observation of overlapping //Q//-branch transitions of the ν<sub>2</sub> band of HCO<sup>+</sup> near 829.2 cm<sup>–1</sup> appears to be not only the first observation of this band in a young stellar object, but probably the first infrared observation of HCO<sup>+</sup> in space.
	+
	+	N. S. Hakobian and R. M. Crutcher\\
	+	detected the\\
	+	[[https://doi.org/10.1088/2041-8205/758/1/L18\|First Interstellar HCO<sup>+</sup> Maser]]\\
	+	//Astrophys. J.// 712, 274–286 (2010)\\
	+	through CARMA observations of its 1 – 0 transition in direction of the DR21(OH)-1 methanol maser region.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 11, 2012
	+
	+	----
	+

hco

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:24:41 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Formyl Radical, HCO, in the ISM =====
	+
	+	HCO is frequently discussed in conjunction with PDRs (photo dissiciation regions). L. E. Snyder, J. M. Hollis, and B. L. Ulich, reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1976ApJ...208L..91S\|Radio Detection of the Interstellar Formyl Radical]]\\
	+	//Astrophys. J.// 208, L91–L94 (1976).\\
	+	The NRAO 11 M dish was used to detect the strongest HFS components (//J// = 1.5 – 0.5, //F// = 2 – 1) of the 1<sub>01</sub> – 0<sub>00</sub> transition near 86.671 GHz in emission toward sources showing carbon recombination lines: W3, W51, NGC 2024C, and K3-50. Please note that the NGC 2024 position was stated more precisely in the follwing paragraph.
	+
	+	J. M. Hollis and E. Churchwell\\
	+	looked at the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1983ApJ...271..170H\|Comparison of C<sup>+</sup> Distributions with new Interstellar Sources of HCO Emission]]\\
	+	//Astrophys. J.// 271, 170–744 (1983).\\
	+	The same HFS component was observed with the same instruments as above. New detections were made at a position close to Sgr B2(OH) and in DR21C.
	+
	+	L. E. Snyder, M. S. Schenewerk, and J. M. Hollis,\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1985ApJ...298..360S\|Observations of Several new Transitions of Interstellar HCO]]\\
	+	//Astrophys. J.// 298, 360–368 (1985).\\
	+	Observations of the 2<sub>02</sub> – 1<sub>01</sub> and 3<sub>03</sub> – 2<sub>01</sub> transitions were made. In addition,\\
	+	Å Hjalmarson, M. S. Schenewerk, and L. E. Snyder,\\
	+	reported on\\
	+	[[https://ui.adsabs.harvard.edu/abs/1985ApJ...298..360S\|Interstellar HCO – Detection of the Missing 3 Millimeter Quartet]]\\
	+	//Astrophys. J.// 298, L71–L74 (1986).
	+
	+	H. S. Liszt, J. Pety, M. Gerin, and R. Lucas,\\
	+	detected with the IRAM 30 m telescope\\
	+	[[https://doi.org/10.1051/0004-6361/201323320\|HCO, //c//-C<sub>3</sub>H and CF<sup>+</sup>: three new molecules in diffuse, translucent and “spiral-arm” clouds]]\\
	+	//Astron. Astrophys.// 564, Art. No. A64 (2014).
	+
	+	The formyl radical is also found quite commonly toward certain types of dark clouds, as found, e.g., by\\
	+	M. Agúndez, J. Cernicharo, and M. Guélin\\
	+	in the report on the\\
	+	[[https://doi.org/10.1051/0004-6361/201526317\|Discovery of Interstellar Ketenyl (HCCO), a Surprisingly Abundant Radical]]\\
	+	//Astron. Astrophys.// 577, Art. No. L5 (2015).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2015
	+
	+	----
	+

hcocn

anonymous@undisclosed.example.com (Anonymous) — Wed, 30 Jun 2021 14:19:29 +0000

2021/06/30 16:09		current
Line 8:		Line 8:
	J. Cernicharo, C. Cabezas, Y. Endo, M. Agúndez, B. Tercero, J. R. Pardo, N. Marcelino, and P. de Vicente\\		J. Cernicharo, C. Cabezas, Y. Endo, M. Agúndez, B. Tercero, J. R. Pardo, N. Marcelino, and P. de Vicente\\
	report on\\		report on\\
-	[[https://doi.org/10.1051/0004-6361/202141297\|The sulphur saga in TMC-1: Discovery of HCSCN and HCSCCH]]\\	+	[[https://doi.org/10.1051/0004-6361/202141297\|The Sulphur Saga in TMC-1: Discovery of HCSCN and HCSCCH]]\\
	//Astron. Astrophys.// 650, Art. No. L14 (2021).\\		//Astron. Astrophys.// 650, Art. No. L14 (2021).\\
		+	Formyl cyanide was indentified besides these two new and several other molecules. HC(O)CN was identified through 2 //a//-type transitions with //K<sub>a</sub>// = 0 and //J// = 4 − 3 or 5 − 4. The identifications were made in the course of an ongoing unbiased molecular line survey between 31.1 and 50.4 GHz using the Yebes 40 m radio telescope. The column density ratio of propynal and formyl cyanide is about 4.\\

	----		----

-	Contributor(s): H. S. P. Müller; 03, 2008	+	Contributor(s): H. S. P. Müller; 03, 2008; 06, 2021

	----		----

hcosh

anonymous@undisclosed.example.com (Anonymous) — Fri, 07 May 2021 13:39:59 +0000

2021/05/07 15:24		current
Line 6:		Line 6:
	C<sub>2</sub>H<sub>5</sub>SH]]**\\		C<sub>2</sub>H<sub>5</sub>SH]]**\\
	//Astrophys. J. Lett.// 912 (2021), Art. No. L11.\\		//Astrophys. J. Lett.// 912 (2021), Art. No. L11.\\
-	Nine rotational transitions (of the trans conformer) with 2 ≤ //J// ≤ 8 and //K<sub>a</sub>// mostly 0 or 1 were shown, of which seven were unblended or marginally blended, two lines were more blended. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. All lines, including the blended ones, were modeled reasonably well employing and LTE fit with //T//<sub>rot</sub> = 10 ± 1 K. The moderate signal-to-noise ratio limits the quality of this fit somewhat; the quoted values range from 13.4 to 6.0. The column density of formic acid is about a factor of 12 higher, that of methanethiol a factor of 40 higher.\\	+	Nine rotational transitions (of the trans conformer) with 2 ≤ //J// ≤ 8 and //K<sub>a</sub>// mostly 0 or 1 were reported and shown, of which seven were unblended or marginally blended, two lines were more blended. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3 mm. All lines, including the blended ones, were modeled reasonably well employing an LTE fit with //T//<sub>rot</sub> = 10 ± 1 K. The moderate signal-to-noise ratio limits the quality of this fit somewhat; the quoted values range from 13.4 to 6.0. The column density of formic acid is about a factor of 12 higher, that of methanethiol a factor of 40 higher.\\

hcp

anonymous@undisclosed.example.com (Anonymous) — Fri, 29 Mar 2019 14:23:16 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of Phosphaethyne, HCP, toward IRC +10216 =====
	+
	+	Phosphaethyne, HCP, has been detected in four successive transitions, //J"// = 3 to 6. In addition, the signal-to-noise ration of the //J// = 2 – 1 is compatible with the intensities of the other transitions:\\
	+	M. Agúndez, J. Cernicharo, and M. Guélin,\\
	+	[[https://doi.org/10.1086/519561\|Discovery of Phosphaethyne (HCP) in Space: Phosphorus Chemistry in Circumstellar Envelopes]]\\
	+	//Astrophys. J.// 662 (2007) L91−L94.\\
	+	HCP is isolelectronic to HCN, and CP had long been detected toward IRC +10216. Therefore, it is somewhat surprising that the detection of this molecule has not been reported earlier. After all, it is quite abundant in this source ! Two reasons have to be considered: first, the dipole moment is fairly small, and second, it seems to be present not far out in the circumstellar envelope, where rotational temperatures are low, but rather in an intermediate region, where its lowest rotational levels are populated less than higher ones.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2007
	+
	+
	+	----
	+

hcs_hsc

anonymous@undisclosed.example.com (Anonymous) — Sun, 21 Nov 2021 15:05:43 +0000

2019/04/23 17:16		current
Line 3:		Line 3:
	M. Agúndez, N. Marcelino, J. Cernicharo, and M. Tafalla,\\		M. Agúndez, N. Marcelino, J. Cernicharo, and M. Tafalla,\\
	used the IRAM 30 m telescope for the\\		used the IRAM 30 m telescope for the\\
-	[[http://dx.doi.org/10.1051/0004-6361/201219379\|Detection of Interstellar HCS and its Metastable Isomer HSC: New Pieces in the Puzzle of Sulfur Chemistry]]\\	+	[[https://doi.org/10.1051/0004-6361/201832743\|Detection of Interstellar HCS and its Metastable Isomer HSC: New Pieces in the Puzzle of Sulfur Chemistry]]\\
	//Astron. Astrophys.// ****, Art. No. L1 (2018).\\		//Astron. Astrophys.// ****, Art. No. L1 (2018).\\
	The //J<sub>Ka</sub>,<sub>Kc</sub>// = 2<sub>0,2</sub> – 1<sub>0,1</sub> transition was detected for both molecules near 81 GHz toward the the young stellar object IRAS 18148–0440 in the L483 dense core. Five hyperfine components of two FS components were detected for HCS with reasonable to very good signal-to-noise ratios. Only two hyperfine components of two FS components were detected for HSC; one observable HFS component was affected by a negative frequency-switching feature of a different molecule. The derived HCS/HSC ratio is about 40, and the H<sub>2</sub>CS/HCS ratio is around 2.		The //J<sub>Ka</sub>,<sub>Kc</sub>// = 2<sub>0,2</sub> – 1<sub>0,1</sub> transition was detected for both molecules near 81 GHz toward the the young stellar object IRAS 18148–0440 in the L483 dense core. Five hyperfine components of two FS components were detected for HCS with reasonable to very good signal-to-noise ratios. Only two hyperfine components of two FS components were detected for HSC; one observable HFS component was affected by a negative frequency-switching feature of a different molecule. The derived HCS/HSC ratio is about 40, and the H<sub>2</sub>CS/HCS ratio is around 2.
Line 11:		Line 11:

	Contributor(s): H. S. P. Müller; 03, 2018		Contributor(s): H. S. P. Müller; 03, 2018
-

	----		----

hcs-plus

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:27:51 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of HCS+ in the ISM =====
	+
	+	The thioformyl cation, HCS<sup>+</sup>, has been observed in the ISM prior to the laboratory by\\
	+	P. Thaddeus, M. Guélin, and R. A. Linke,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1981ApJ...246L..41T\|Three New 'Nonterrestrial' Molecules]]\\
	+	//Astrophys. J.// 246, L41–L45 (1981).\\
	+	The //J// = 2 – 1 transition near 85.3 GHz was detected toward the hot-core sources Orion KL, Sgr B2(OH), and DR 21 as well as toward the dense cold cloud TMC-1. In addition, the 3 – 2, 5 – 4, and 6 – 5 transitions were also detected in Orion KL.
	+
	+	The molecular cation was also detected in several translucent molecular clouds by\\
	+	B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1996ApJ...461..246T\|The Physics and Chemistry of Small Translucent Molecular Clouds. VI. Organo-Sulfur Species]]\\
	+	//Astrophys. J.// 416, 246–264 (1996)
	+
	+	The 7 – 6, and 8 – 7 transitions were detected in a PDR by\\
	+	S. Leurini, R. Rolffs, S. Thorwirth, B. Parise, P. Schilke, C. Comito, F. Wyrowski, R. Güsten, P. Bergman, K. M. Menten, and L.-Å. Nyman,\\
	+	[[https://doi.org/10.1051/0004-6361:20065555\|APEX 1 mm Line Survey of the Orion Bar]]\\
	+	//Astron. Astrophys.// 454, L47–L50 (2006)
	+
	+	A. Fuente, J. Cernicharo, E. Roueff, M. Gerin, J. Pety, N. Marcelino, R. Bachiller, B. Lefloch, O. Roncero, and A. Aguado,\\
	+	studied the\\
	+	[[https://doi.org/10.1051/0004-6361/201628285\|Ionization Fraction and the Enhanced Sulfur Chemistry in Barnard 1]]\\
	+	//Astron. Astrophys.// 593, Art. No. A94 (2016).\\
	+	They used the IRAM 30 m telescope for a molecular line survey at 3, 2, and 1.3 mm. The //J// = 3 – 2 transition of DCS<sup>+</sup> at 108.108 GHz was detected in emission. An LVG analysis suggests a D/H ratio of almost 0.1 in the region in which the DCS<sup>+</sup> emission was detected.
	+
	+	A. Potapov, Á. Sánchez-Monge, P. Schilke, U. U. Graf, T. Möller, and S. Schlemmer\\
	+	reported almost at the same time on the detection of the same transition in their search for\\
	+	[[https://doi.org/10.1051/0004-6361/201628426\|The CO–H<sub>2</sub> van der Waals complex and complex organic molecules in cold molecular clouds: A TMC-1C survey]]\\
	+	//Astron. Astrophys.// 594, Art. No. A117 (2016).\\
	+	The IRAM 30 m telescope was used once more.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2003; 09, 2011; 11, 2016
	+
	+	----
	+

hcscn

anonymous@undisclosed.example.com (Anonymous) — Wed, 30 Jun 2021 15:10:31 +0000

2021/06/30 16:56		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202141297\|The Sulphur Saga in TMC-1: Discovery of HCSCN and HCSCCH]]\\		[[https://doi.org/10.1051/0004-6361/202141297\|The Sulphur Saga in TMC-1: Discovery of HCSCN and HCSCCH]]\\
	//Astron. Astrophys.// 650, Art. No. L14 (2021).\\		//Astron. Astrophys.// 650, Art. No. L14 (2021).\\
-	Cyanothioformaldehyde, aka thioformyl cyanide, was identified through 10 unblended or only slightly blended //a//-type transitions with 4 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 30.1 and 50.4 GHz. A value of //T//<sub>rot</sub> = 5.0 K was assumed, in keeping with cyanothioformaldehyde. The column density of HC<sub>2</sub>CHS is about a factor of 5 lower than that of the isovalent HC<sub>2</sub>CHO, similar to the corresponding factor of 10 between thioformaldehyde and formaldehyde. In addition, the column density of HC<sub>2</sub>CHS is about a factor of 4 lower than that of the isoelectronic HC(S)CN; the latter molecule is unusually abundant in TMC-1.\\	+	Cyanothioformaldehyde, aka thioformyl cyanide, was identified through 10 unblended or only slightly blended //a//-type transitions with 4 ≤ //J// ≤ 8 and //K<sub>a</sub>// ≤ 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 30.1 and 50.4 GHz. Also observed were 9 much weaker //b//-type transitions with 1 ≤ //J// ≤ 9 and //K<sub>a</sub>// ≤ 1; some of these were blended, and several were affected by low signal-to-noise ratios. A value of //T//<sub>rot</sub> = 5.0 ± 0.5 K was derived. The column density of HC(S)CN is unusually high compared to related molecules. It is about a factor of 4 higher than that of the isovalent HC(O)CN, whereas the one of HC<sub>2</sub>CHS is about a factor of 5 lower than that of HC<sub>2</sub>CHO, similar to the corresponding factor of 10 between thioformaldehyde and formaldehyde.\\

hcxn-plus

anonymous@undisclosed.example.com (Anonymous) — Thu, 25 Sep 2025 15:00:04 +0000

2024/07/31 16:17		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202450801\|QUIJOTE discovery of the cation radicals HC5N+ and HC7N+]]\\		[[https://doi.org/10.1051/0004-6361/202450801\|QUIJOTE discovery of the cation radicals HC5N+ and HC7N+]]\\
	//Astron. Astrophys.// 686, Art. No. L15 (2024).\\		//Astron. Astrophys.// 686, Art. No. L15 (2024).\\
-	HC<sub>5</sub>N<sup>+</sup> and HC<sub>7</sub>N<sup>+</sup> were identified through 7 and 8 unblended or slightly blended transitions in their <sup>2</sup>Π<sub>3/2</sub> lower spin ladder, respectively, with 23/2 ≤ //J// ≤ 37/2 in the first case and 53/2 ≤ //J// ≤ 69/2 in the latter. The identifications were made in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. //T//<sub>rot</sub> = 8.5 ± 0.5 K was derived for HC<sub>5</sub>N<sup>+</sup>, while //T//<sub>rot</sub> = 7.8 ± 0.1 K was derived for HC<sub>7</sub>N<sup>+</sup>. The abundance ratios present a consistent and interesting picture. The HC<sub>5</sub>N<sup>+</sup> / HC<sub>7</sub>N<sup>+</sup> ratio is ~4.2; the HC<sub>5</sub>N<sup>+</sup> / HC<sub>5</sub>N, HC<sub>5</sub>N<sup>+</sup> / C<sub>5</sub>N<sup>−</sup>, and HC<sub>5</sub>N<sup>+</sup> / C<sub>5</sub>N<sup>−</sup> ratios are about 670, 4.8, and 1.2, respectively, while the HC<sub>7</sub>N<sup>+</sup> / HC<sub>7</sub>N and HC<sub>7</sub>N<sup>+</sup> / C<sub>7</sub>N<sup>−</sup> ratios are about 1000 and 2.2, respectively.\\	+	HC<sub>5</sub>N<sup>+</sup> and HC<sub>7</sub>N<sup>+</sup> were identified through 7 and 8 unblended or slightly blended transitions in their <sup>2</sup>Π<sub>3/2</sub> lower spin ladder, respectively, with 23/2 ≤ //J// ≤ 37/2 in the first case and 53/2 ≤ //J// ≤ 69/2 in the latter. The identifications were made in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz. //T//<sub>rot</sub> = 8.5 ± 0.5 K was derived for HC<sub>5</sub>N<sup>+</sup>, while //T//<sub>rot</sub> = 7.8 ± 0.1 K was derived for HC<sub>7</sub>N<sup>+</sup>. The abundance ratios present a consistent and interesting picture. The HC<sub>5</sub>N<sup>+</sup> / HC<sub>7</sub>N<sup>+</sup> ratio is ~4.2; the HC<sub>5</sub>N / HC<sub>5</sub>N<sup>+</sup>, C<sub>5</sub>N / HC<sub>5</sub>N<sup>+</sup>, and C<sub>5</sub>N<sup>−</sup> / HC<sub>5</sub>N<sup>+</sup> ratios are about 670, 4.8, and 1.2, respectively, while the HC<sub>7</sub>N / HC<sub>7</sub>N<sup>+</sup> and C<sub>7</sub>N<sup>−</sup> / HC<sub>7</sub>N<sup>+</sup> ratios are about 1000 and 2.2, respectively.\\
	\\		\\

heh-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 12 May 2020 11:37:11 +0000

2019/04/24 12:35		current
Line 2:		Line 2:

	R. Güsten, H. Wiesemeyer, D. Neufeld, K. M. Menten, U. U. Graf, K. Jacobs,		R. Güsten, H. Wiesemeyer, D. Neufeld, K. M. Menten, U. U. Graf, K. Jacobs,
-	B. Klein, O. Ricken, C. Risacher, and J. Stutzki,\\	+	B. Klein, O. Ricken, C. Risacher, and J. Stutzki\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.1038/s41586-019-1090-x\|Astrophysical detection of the helium hydride ion HeH<sup>+</sup>]]\\		[[https://doi.org/10.1038/s41586-019-1090-x\|Astrophysical detection of the helium hydride ion HeH<sup>+</sup>]]\\
Line 11:		Line 11:
	calculations; interestingly, about a factor of four was detected compared to		calculations; interestingly, about a factor of four was detected compared to
	the expectations.\\		the expectations.\\
-	See also the [[http://www.mpifr-bonn.mpg.de/pressreleases/2019/5\|MPIfR press release]] (in English; [[https://www.mpifr-bonn.mpg.de/pressemeldungen/2019/5\|German version]] also available).	+	See also the [[https://www.mpifr-bonn.mpg.de/pressreleases/2019/5\|MPIfR press release]] (in English; [[https://www.mpifr-bonn.mpg.de/pressemeldungen/2019/5\|German version]] also available).\\

		+
		+	D. A. Neufeld, M. Goto, T. R. Geballe, R. Güsten, K. M. Menten, and H. Wiesemeyer\\
		+	reported on the\\
		+	[[https://doi.org/10.3847/1538-4357/ab7191\|Detection of Vibrational Emissions from the Helium Hydride Ion (HeH<sup>+</sup>) in the Planetary Nebula NGC 7027]]\\
		+	//Astrophys. J.// 894, Art. No. 37 (2020).\\
		+	The //v// = 1 − 0, //P//(1) and //P//(2) transitions were detected near 3.5 and 3.6 μm, respectively, using the iSHELL spectrograph at the Infrared Telescope Facility on Mauna Kea. Their best source model reproduced the //P//(1) flux very well, but underproduced the fluxes of the //P//(2) and rotational transitions.\\

	----		----

-	Contributor(s): H. S. P. Müller; 04, 2019	+	Contributor(s): H. S. P. Müller; 04, 2019; 05, 2020

hf

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:59:49 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Hydrogen Fluoride, HF, in Space =====
	+
	+	The //J// = 2 – 1 transition HF was detected in absorption toward Sgr B2 with the Long Wavelength Spectrometer of the ISO satellite:\\
	+	D. A. Neufeld, J. Zmuidzinas, P. Schilke, and T. G. Phillips,\\
	+	[[https://doi.org/10.1086/310942\|Discovery of Interstellar Hydrogen Fluoride]]\\
	+	//Astrophys. J.// 488, L141–L144 (1997).
	+
	+	The //J// = 1 – 0 transition was observed with the HIFI instrument of the //Herschel// satellite toward G10.6-0.4 (W31C) and Orion KL. Absorption dominates in the former case, but also, very surprisingly, in the latter:\\
	+	D. A. Neufeld, P. Sonnentrucker, T. G. Phillips, et al.,\\
	+	[[https://doi.org/10.1051/0004-6361/201014523\|Strong Absorption by Interstellar Hydrogen Fluoride: //Herschel///HIFI Observations of the Sight-Line to G10.6–0.4 (W31C)]]\\
	+	//Astron. Astrophys.// 518, Art. No. L108 (2010);\\
	+	T. G. Phillips, E. A. Bergin, D. C. Lis, et. al.,\\
	+	[[https://doi.org/10.1051/0004-6361/201014570\|//Herschel// Observations of EXtra-Ordinary Sources (HEXOS): Detection of Hydrogen Fluoride in Absorption towards Orion KL]]\\
	+	//Astron. Astrophys.// 518, Art. No. L109 (2010).
	+
	+	The same transition was also detected in the circumstellar envelope of the carbon rich star CW Leo by:\\
	+	M. Agúndez, J. Cernicharo, L. B. F. M. Waters, L. Decin, P. Encrenaz, D. Neufeld, D. Teyssier, and F. Daniel,\\
	+	[[https://doi.org/10.1051/0004-6361/201117578\|HIFI detection of Hydrogen Fluoride in the Carbon Star Envelope IRC +10216]]\\
	+	//Astron. Astrophys.// 533, Art. No. L6 (2011).
	+
	+	More recently this transition has even been detected in emission in the photon-dominated region by:\\
	+	F. F. S. van der Tak, V. Ossenkopf, Z. Nagy, A. Faure, M. Röllig, and E. A. Bergin,\\
	+	[[https://doi.org/10.1051/0004-6361/201118308\|Detection of HF Emission from the Orion Bar]]\\
	+	//Astron. Astrophys.// 537, Art. No. L10 (2012).
	+
	+	The //R//(0) rovibrational transition of HF at 4000.989 cm<sup>–1</sup> or 2.499385 μm was detected with CRIRES at the Very Large Telescope in absorption toward V1074 Sco, aka HD 154368, and Elias 29 by:\\
	+	N. Indriolo, D. A. Neufeld, A. Seifahrt, and M. J. Richter,\\
	+	[[https://doi.org/10.1088/0004-637X/764/2/188\|Direct Determination of the HF/H<sub>2</sub> Abundance Ratio in Interstellar Gas]]\\
	+	//Astrophys. J.// 764, Art. No. 188 (2013).\\
	+	//R//(0) as well as //R//(1) were also detected toward AFGL 2136 IRS 1.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 03, 2007; 12, 2010; 08, 2011; 07, 2012; 11, 2013
	+
	+	----
	+

hmgc3n

anonymous@undisclosed.example.com (Anonymous) — Mon, 08 May 2023 14:30:15 +0000

2023/05/08 16:21		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202346462\|Discovery of Two Metallic Cyanoacetylides in IRC +10216: HMgCCCN and NaCCCN]]\\		[[https://doi.org/10.1051/0004-6361/202346462\|Discovery of Two Metallic Cyanoacetylides in IRC +10216: HMgCCCN and NaCCCN]]\\
	//Astron. Astrophys.// 672, Art. No. L12 (2023).\\		//Astron. Astrophys.// 672, Art. No. L12 (2023).\\
-	The molecule was identified in the course of a molecular line survey between 31.0 and 50.3 GHz through four unblendand two slightly blended transitions. One further line was heavily blended and the one at highest frequency was slightly too weak to be observed.	+	The molecule was identified in the course of a molecular line survey with the 40 m Yebes radio telescope between 31.0 and 50.3 GHz through four unblend and two slightly blended transitions. One further line was heavily blended and the one at highest frequency was slightly too weak to be observed.
	The identification relied on quantum chemical calculations in the absense of laboratory spectroscopic data. The rotational temperature is roughly 17 K. The abundance ratios of HMgC<sub>3</sub>N : MgCN : MgC<sub>3</sub>N : MgC<sub>5</sub>N : MgNC : HMgNC are about 30 : 7.4 : 93 : 47 : 130 : 6.\\		The identification relied on quantum chemical calculations in the absense of laboratory spectroscopic data. The rotational temperature is roughly 17 K. The abundance ratios of HMgC<sub>3</sub>N : MgCN : MgC<sub>3</sub>N : MgC<sub>5</sub>N : MgNC : HMgNC are about 30 : 7.4 : 93 : 47 : 130 : 6.\\

hmgnc

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:10:31 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	After charaterization of its rotational spectrum by Fourier microwave spectroscopy, magnesium hydride isocyanide, or hydridomagnesium isocyanide, HMgNC, was identified in the circumstellar envelope of the late-type carbon-rich star CW Leonis, also known as IRC +10216 by\\		After charaterization of its rotational spectrum by Fourier microwave spectroscopy, magnesium hydride isocyanide, or hydridomagnesium isocyanide, HMgNC, was identified in the circumstellar envelope of the late-type carbon-rich star CW Leonis, also known as IRC +10216 by\\
	C. Cabezas, J. Cernicharo, J. L. Alonso, M. Agúndez, S. Mata, M. Guélin, and I. Peña,\\		C. Cabezas, J. Cernicharo, J. L. Alonso, M. Agúndez, S. Mata, M. Guélin, and I. Peña,\\
-	[[http://dx.doi.org/10.1088/0004-637X/775/2/133\|Laboratory and Astronomical Discovery of HydroMagnesium Isocyanide]]\\	+	[[https://doi.org/10.1088/0004-637X/775/2/133\|Laboratory and Astronomical Discovery of HydroMagnesium Isocyanide]]\\
	//Astrophys. J.// 775, Art. No. 133 (2013).\\		//Astrophys. J.// 775, Art. No. 133 (2013).\\
	Five rotational transitions, //J"// = 7 to 9 and 11 and 12 were observable in theory between 87 and 143 GHz in the course of a molecular line survey carried out with the IRAM 30 m radiotelecope on Pico Veleta, Spain. //J"// = 7 and 9 were seen with reasonable signal-to-noise ratio. //J"// = 8 was fully overlapped, and //J"// = 11 and 12 were overlapped in part, but could be included in the analysis. The rotational temperature of around 21 K is similar to that of MgNC and maybe slightly warmer than that of MgCN. Its column density is slightly smaller than that of MgCN, and much smaller, by a factor of about 20, than that of MgNC.		Five rotational transitions, //J"// = 7 to 9 and 11 and 12 were observable in theory between 87 and 143 GHz in the course of a molecular line survey carried out with the IRAM 30 m radiotelecope on Pico Veleta, Spain. //J"// = 7 and 9 were seen with reasonable signal-to-noise ratio. //J"// = 8 was fully overlapped, and //J"// = 11 and 12 were overlapped in part, but could be included in the analysis. The rotational temperature of around 21 K is similar to that of MgNC and maybe slightly warmer than that of MgCN. Its column density is slightly smaller than that of MgCN, and much smaller, by a factor of about 20, than that of MgNC.
Line 11:		Line 11:

	Contributor(s): H. S. P. Müller; 09, 2013		Contributor(s): H. S. P. Müller; 09, 2013
-

	----		----

hnc

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:32:23 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on Hydrogen Isocyanide in the ISM/CSM =====
	+
	+	Hydrogen isocyanide, HNC was among the early molecules detected in space. Moreover, it was one of the molecules detected in space before laboratory spectroscopic information was available for its identification. Two reports appeared at about the same time.\\
	+	L. E. Snyder and D. Buhl,\\
	+	reported on the\\
	+	[[https://doi.org/10.1111/j.1749-6632.1972.tb12687.x\|Detection of Several new Interstellar Molecules]]\\
	+	//Ann. N Y Acad. Sci.// 194, 17–24 (1972).\\
	+	An emission line at 90.665 GHz was detected with the 11 m radio telescope of the NRAO toward the massive star-forming regions Sgr B2 and W 51 as well as toward the hot core DR21(OH). The line was assigned somewhat tentatively to the //J// = 1&nbsp:– 0 transition of HNC.\\
	+	B. Zuckerman, M. Morris, P. Palmer, and B. E. Turner,\\
	+	also used the 11 m radio telescope of the NRAO for\\
	+	[[https://ui.adsabs.harvard.edu/abs/1972ApJ...173L.125Z\|Observations of CS, HCN, U89.2, and U90.7 in NGC 2264]]\\
	+	//Astrophys. J.// 173, L125–L129 (1972).\\
	+	NGC 2264 is a Galactic open cluster and may, as broader source type, be viewed as photon-dominated region (PDR). U90.7 was not assigned here.\\
	+	The molecule was identified unambiously by the laboratory work of\\
	+	G. L. Blackman, R. D. Brown, P. D. Godfrey, and H. I. Gunn,\\
	+	[[https://doi.org/10.1038/261395a0\|The Microwave Spectrum of HNC: Identification of U90.7]]\\
	+	//Nature// 261, 395–396 (1976).
	+
	+	R. D. Brown, P. D. Godfrey, J. W. V. Storey, and F. O. Clark, reported on\\
	+	[[http://dx.doi.org/10.1038/262672a0\|Detection of Interstellar HN<sup>13</sup>C]]\\
	+	//Nature// 262, 672–674 (1976).\\
	+	The 11 m radio telescope of the NRAO was used to detect //J// = 1&nbsp:– 0 transition of this isotopolog near 87.1 GHz and of the main isotopolog toward W 51, Sgr B2 and DR21(HCN peak).\\
	+	The authors also reported the detection of HNC toward the circumstellar envelope of the carbon-star CW Leo, aka IRC +10216; the detection of HN<sup>13</sup>C in that source was tentative.
	+
	+	R. D. Brown, P. D. Godfrey, H. I. Gunn, G. L. Blackman, and J. W. V. Storey published\\
	+	[[https://ui.adsabs.harvard.edu/abs/1977MNRAS.180P..83G\|Detection of Interstellar DNC – Difficulties of Chemical Equilibrium Hypothesis for Enrichment]]\\
	+	//Mon. Not. R. Astr. Soc.// 180, 83–86 (1977).\\
	+	The //J// = 1&nbsp:– 0 transition near 76.3 GHz was detected toward NGC 2264 again with the 11 m radio telescope of the NRAO.\\
	+	Shortly thereafter, the //J// = 2&nbsp:– 1 transition near 152.6 GHz was detected with the 5 m MWO radio telescope towards a diverse ensemble of sources: NGC&nb1p;1333, Ori A, NGC 2264, and L134 by\\
	+	R. L. Snell and H. A. Wootten,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1977ApJ...216L.111S\|Detection of Interstellar DNC]]\\
	+	//Astrophys. J.// 216, L111–L114 (1977).\\
	+
	+
	+	HNC was also detected toward dark clouds:\\
	+	L. E. Snyder and J. M. Hollis,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1976ApJ...204L.139S\|HCN, X-ogen (HCO<sup>+</sup>), and U90.66 Emission Spectra from L134]]\\
	+	//Astrophys. J.// 204, L139–L142 (1976).
	+
	+	HNC was detected in the complete set of 38 translucent clouds (11 cirrus, 27 CB) in which it was searched for by:\\
	+	B. E. Turner, L. Pirogov, and Y. C. Minh,\\
	+	[[https://doi.org/10.1086/304228\|The Physics and Chemistry of Small Translucent Molecular Clouds. VIII. HCN and HNC]]\\
	+	//Astrophys. J.// 483, 235–261 (1997).\\
	+	DNC was also found in CB 17 by:\\
	+	B. E. Turner,\\
	+	[[https://doi.org/10.1086/322536\|Deuterated Molecules in Translucent and Dark Clouds]]\\
	+	//Astrophys. J. Suppl. Ser.// 136, 579–629 (2001).\\
	+
	+
	+	HNC was also seen in absorption in diffuse clouds:\\
	+	H. Liszt and R. Lucas,\\
	+	[[https://doi.org/10.1051/0004-6361:20010260\|Comparative Chemistry of Diffuse Clouds. II. CN, HCN, HNC, CH<sub>3</sub>CN, and N<sub>2</sub>H<sup>+</sup>]]\\
	+	//Astron. Astrophys.// 370, 576–585 (2001).
	+
	+	Rotational transitions of HNC in its //v//<sub>2</sub> = 1 excited vibrational state have been detected in the protoplanetary nebula V353 Aur, also known as CRL 618, by:\\
	+	P. Schilke, C. Comito, and S. Thorwirth,\\
	+	[[https://doi.org/10.1086/367628\|First Detection of Vibrationally Excited HNC in Space]]\\
	+	//Astrophys. J.// 582, L101–L104 (2003).\\
	+	The CSO was used to detect both //l//-components of the //J// = 3 – 2 and 4 – 3 transitions.
	+
	+	J. Cernicharo, F. Daniel, A. Castro-Carrizo, M. Agundez, N. Marcelino, C. Joblin, J. R. Goicoechea, and M. Guélin\\
	+	were\\
	+	[[https://doi.org/10.1088/2041-8205/778/2/L25\|Unveiling the Dust Nucleation Zone of IRC+10216 with ALMA]]\\
	+	//Astrophys. J.// 778, Art. No. L25 (2013).\\
	+	In the process, they detected emission pertaining to several //J// = 3 – 2 transition in excited vibrational states up to the CH stretching mode with //E//<sub>vib</sub> of about 5300 K in the circumstellar envelope of CW Leonis. Even higher states will likely be detected with longer integration time or more dishes. The observations were made in cycle 0.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 04, 2012; 01, 2014
	+
	+	----
	+

hnc3

anonymous@undisclosed.example.com (Anonymous) — Mon, 08 Apr 2024 15:59:09 +0000

2024/04/08 17:52		current
Line 26:		Line 26:
	//Astron. Astrophys.// 642, Art. No. L8 (2020).\\		//Astron. Astrophys.// 642, Art. No. L8 (2020).\\
	The authors report the detection of DNC<sub>3</sub>. The observations were obtained with the Yebes 40m radio telescope in the course of a line survey covering 31.0–50.3 GHz.\\		The authors report the detection of DNC<sub>3</sub>. The observations were obtained with the Yebes 40m radio telescope in the course of a line survey covering 31.0–50.3 GHz.\\
		+	\\
		+
		+	J. Cernicharo, B. Tercero, C. Cabezas, M. Agúndez, E. Roueff, R. Fuentetaja, N. Marcelino, and P. de Vicente\\
		+	carried out more recently a\\
		+	[[https://doi.org/10.1051/0004-6361/202348822\|Study of the HCCNC and HNCCC isotopologs in TMC-1]]\\
		+	//Astron. Astrophys.// 682, Art. No. L13 (2024).\\
		+	They reported in the framework of improved data of the above survey the detection of the three HNC<sub>3</sub> <sup>13</sup>C isotopomers. They determined the <sup>12</sup>C/<sup>13</sup>C ratios of ~90 with scatter that is insignificant with respect to the uncertainties. These values are somewhat lower than ~65 usually found in the the local ISM, but very similar to values of HCCNC <sup>13</sup>C isotopomers and to two of the three HC<sub>3</sub>N <sup>13</sup>C isotopomers. In addition, an H/D ratio of ~53 was reported, similar to the value of 57 ± 2 of HC<sub>3</sub>N.\\
	\\		\\

hnc5

anonymous@undisclosed.example.com (Anonymous) — Thu, 15 Aug 2024 14:00:31 +0000

2024/08/15 15:45		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202451319\|Space and laboratory discovery of iminopentadienylidene, HNC5]]\\		[[https://doi.org/10.1051/0004-6361/202451319\|Space and laboratory discovery of iminopentadienylidene, HNC5]]\\
	//Astron. Astrophys.// 688, Art. No. L29 (2024).\\		//Astron. Astrophys.// 688, Art. No. L29 (2024).\\
		+	The molecule was detected in the course of the QUIJOTE line survey of the dark cloud TMC-1 with the Yebes 40 m dish through six rotational transitions between 32.6 and 46.3 GHz having 11 ≤ //J// ≤ 17 with good to reasonable signal-to-noise ratios. A rotational tempertaure of 6.0 ± 0.5K was derived. The column density ratios are about 45 : 1 for HNC<sub>3</sub> : HNC<sub>5</sub> and about 5100 : 10 : 1 for HC<sub>5</sub>N : HC<sub>4</sub>NC : HNC<sub>5</sub>.\\
		+	\\

		+	----
		+
		+	Contributor(s): H. S. P. Müller; 08, 2024
		+
		+	----

hncn

anonymous@undisclosed.example.com (Anonymous) — Wed, 25 May 2022 13:56:31 +0000

2021/08/24 12:17		current
Line 5:		Line 5:
	[[https://doi.org/10.1093/mnrasl/slab074\|Detection of the Cyanomidyl Radical (HNCN): a new Interstellar Species with the NCN Backbone]]\\		[[https://doi.org/10.1093/mnrasl/slab074\|Detection of the Cyanomidyl Radical (HNCN): a new Interstellar Species with the NCN Backbone]]\\
	//Mon. Not. R. Astron. Soc. Lett.// 506, L79 − L84 (2021).\\		//Mon. Not. R. Astron. Soc. Lett.// 506, L79 − L84 (2021).\\
-	The cyanoamidogen radical, HNCN, was identified in the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes. Transitions (//N// + 1) → //N// with and //K<sub>a</sub>// = 0 and //N// = 1 and 3 to 6 were covered. The two fine structure (FS) components of the //N// = 5 transition and possibly the //J// = 2.5 FS component of the //N// = 3 transition are unblended. The //J// = 3.3 FS component of the //N// = 4 transition is slightly blended, and the astronomical feature is modeled well. All other covered lines are blended more severely. The detection is probably fairly secure because of the low rotational temperature of ~9 K desite the somewhat small number of unblended or slightly blended lines. Nevertheless, some caution may be advised. The //N// = 7 transition was barely missed, but it may already be too weak. The //N// = 2 transition is probably not observable from the ground. The //N// = 1 transition is likely again weak, possibly even more so because of <sup>1</sup>H or <sup>14</sup>N hyperfine structure. The column density is about a factor of 22 lower than that of H<sub>2</sub>NCN.\\	+	The cyanoamidogen radical, HNCN, was identified in the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes. Transitions (//N// + 1) → //N// with and //K<sub>a</sub>// = 0 and //N// = 1 and 3 to 6 were covered. The two fine structure (FS) components of the //N// = 5 transition and possibly the //J// = 2.5 FS component of the //N// = 3 transition are unblended. The //J// = 3.3 FS component of the //N// = 4 transition is slightly blended, and the astronomical feature is modeled well. All other covered lines are blended more severely. The detection is probably fairly secure because of the low rotational temperature of ~9 K desite the somewhat small number of unblended or slightly blended lines. Nevertheless, some caution may be advised. The //N// = 7 transition was barely missed, but it may already be too weak. The //N// = 2 transition is probably not observable from the ground. The //N// = 1 transition is likely again weak, possibly even more so because of potentially resolvable <sup>1</sup>H or <sup>14</sup>N hyperfine structure. The column density is about a factor of 22 lower than that of H<sub>2</sub>NCN.\\


Line 12:		Line 11:

	Contributor(s): H. S. P. Müller; 08, 2021		Contributor(s): H. S. P. Müller; 08, 2021
-

	----		----

hncnh

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:17:44 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Reports on Carbodiimide, HNCNH, in the ISM =====
	+
	+	Carbodiimide, HNCNH, is a high energy isomer (1400 cm<sup>–1</sup> or 2000 K) of the fairly typical hot core molecule cyanamide, H<sub>2</sub>NCN. The molecule is thus very hard to detect under local thermodynamic equilibrium (LTE) conditions. Nevertheless,\\
	+	B. A. McGuire, R. A. Loomis, C. M. Charness, J. F. Corby, G. A. Blake, J. M. Hollis, F. J. Lovas, P. R. Jewell, and A. J. Remijan,\\
	+	reported on\\
	+	[[https://doi.org/10.1088/2041-8205/758/2/L33\|Interstellar Carbodiimide (HNCNH): A New Astronomical Detection from the GBT PRIMOS Survey via Maser Emission Features]]\\
	+	//Astrophys. J.// 758, Art. No. L33 (2012).\\
	+	The molecule displays tunneling splitting into two components separated by slightly less than 0.5 GHz. Four and a half pairs of transitions of the type //J//+1<sub>0,//J//+1</sub> ↔ //J//<sub>1,//J//</sub> with //J// between 15 and 19 would fall into the range of the 1–46 GHz line survey of Sagittarius B2(N), the frequencies of one pair (//J// = 16), however, fall into the 16–17 GHz gap. Both components were seen for //J// = 17 and 18, one for //J// = 19. The maser activity was explained by the energy level structure and the Einstein //A// values. No maser activity was expected and seen for the //J// = 15, and no maser activity is expected for //J// = 16. The authors also suggest that HNCNH is chemically enhanced with respect to the gas phase equilibrium with H<sub>2</sub>NCN either via evaporation from water ice or via non-LTE formation in the gas phase (possibly via dissociative recombination of cations such as H<sub>2</sub>NCNH<sup>+</sup>).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2012
	+
	+	----
	+

hnso

anonymous@undisclosed.example.com (Anonymous) — Wed, 17 Apr 2024 11:21:34 +0000

2024/04/17 13:07		current
Line 3:		Line 3:
	M. Sanz-Novo, V. M. Rivilla, H. S. P. Müller, I. Jiménez-Serra, J. Martín-Pintado, L. Colzi, S. Zeng, A. Megías, Á. López-Gallifa, A. Martínez-Henares, B. Tercero, P. de Vicente, D. San Andrés, S. Martín, and M. A. Requena-Torres\\		M. Sanz-Novo, V. M. Rivilla, H. S. P. Müller, I. Jiménez-Serra, J. Martín-Pintado, L. Colzi, S. Zeng, A. Megías, Á. López-Gallifa, A. Martínez-Henares, B. Tercero, P. de Vicente, D. San Andrés, S. Martín, and M. A. Requena-Torres\\
	announced the\\		announced the\\
		+	[[https://doi.org/10.3847/2041-8213/ad3945\|Discovery of Thionylimide, HNSO, in Space: The first N-, S-, and O-bearing Interstellar Molecule]]\\
		+	//Astrophys. J. Lett.// 965, Art. No. L26 (2024).\\
		+	HNSO was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes. The //a//-type transitions cover 34 to 171 GHz with 1 ≤ //J// ≤ 10 and //K<sub>a</sub>// ≤ 2. Six lines were deemed to be unblended, and 12 more were only slightly blended. An excitation temperature of ~12 K was derived. The molecule is slightly more abundant than the somewhat related HNCS molecule. SO and SO<sub>2</sub> are more abundant by factors of ~38 and ~5, respectively, while NS is ~3.5 times more abundant. The higher energy isomer HSNO was not detected.\\
		+	\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 04, 2024
		+
		+	----

ho2

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:40:41 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of the Hydroperoxyl Radical, HO2, in the ISM =====
	+
	+	B. Parise, P. Bergman, and F. Du,\\
	+	used the IRAM 30 m and the APEX 12 m radio telescopes for the\\
	+	[[https://doi.org/10.1051/0004-6361/201219379\|Detection of the Hydroperoxyl Radical HO<sub>2</sub> toward //ρ// Ophiuchi A: Additional Constraints on the Water Chemical Network]]\\
	+	//Astron. Astrophys.// 541, Art. No. L11 (2012).\\
	+	The //J<sub>K<sub>a</sub>,K<sub>c</sub></sub>// = 2<sub>0,2</sub> – 1<sub>0,1</sub> and 4<sub>0,4</sub> – 3<sub>0,3</sub> around 130.35 and 260.67 GHz, respectively, were detected. Both transitions displayed fine structure splitting of about 200 MHz. In addition, H-hyperfine splitting was resolved for the lower quantum number transition.\\
	+	The source is the same in which H<sub>2</sub>O<sub>2</sub> was detected and the tentative detection of O<sub>2</sub> was confirmed very recently. The column density of HO<sub>2</sub> is very similar to that of H<sub>2</sub>O<sub>2</sub>, in reasonable agreement with model calculations.\\
	+
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2012
	+
	+
	+	----
	+

hoco-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:42:45 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of HOCO+ in Space =====
	+
	+	Oxohydroxymethylium, aka protonated carbon dioxide, HOCO<sup>+</sup>, was among the molecules that had been identified in space (toward the star-forming region Sgr B2(OH)) before they had been characterized in the laboratory. Three transitions //J//+1<sub>0,//J//+1</sub> – //J//<sub>0,//J//</sub> with //J// = 3 – 5 were reported by\\
	+	P. Thaddeus, M. Guélin, and R. A. Linke,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1981ApJ...246L..41T\|Three new 'nonterrestrial' molecules]]\\
	+	//Astrophys. J.// 246, L41–L45 (1981). HOCO<sup>+</sup> or HOCN were seen as possible carriers of these lines. Subsequent laboratory spectroscopic investigations proved the carrier to be HOCO<sup>+</sup>:\\
	+	M. Bogey, C. Demuynck, and J. L. Destombes,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1984A%26A...138L..11B\|Laboratory Detection of the Protonated Carbon Dioxide by Submillimeter Wave Spectroscopy]]\\
	+	//Astron. Astrophys.// 138, L11–L12 (1984).
	+
	+	The molecular ion was also detected toward Sgr A:\\
	+	Y. C. Mihn, W. M. Irvine, and L. M. Ziurys,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1988ApJ...334..175M\|Observations of Interstellar HOCO<sup>+</sup> – Abundance Enhancements toward the Galactic Center]]\\
	+	//Astrophys. J.// 334, 175–181 (1988).
	+
	+	It is also present in dark clouds, such as TMC-1 and L183, as well as in two out of three translucent clouds (CB 17 and CB 228):\\
	+	B. E. Turner, R. Terzieva, and E. Herbst,\\
	+	[[https://doi.org/10.1086/307300\|The Physics and Chemistry of Small Translucent Molecular Clouds. XII. More Complex Species Explainable by Gas-Phase Processes]]\\
	+	//Astrophys. J.// 518, 699–732 (1999).
	+
	+	More recently, it was shown that the ion is not confined to massive star-forming regions:\\
	+	N. Sakai, T. Sakai, Y. Aikawa, and S. Yamamoto,\\
	+	[[https://doi.org/10.1086/533463\|Detection of HCO<sub>2</sub><sup>+</sup> toward the Low-Mass Protostar IRAS 04368+2557 in L1527]]\\
	+	//Astrophys. J.// 675, L89–L92 (2008).
	+
	+	C. Vastel, C. Ceccarelli, B. Lefloch, and R. Bachiller,\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201628427\|Abundance of HOCO<sup>+</sup> and CO<sub>2</sub> in the Outer Layers of the L1544 Prestellar Core]]\\
	+	//Astron. Astrophys.// 691, Art. No. L2 (2016).\\
	+	They report the detection of the 5<sub>05</sub> – 4<sub>04</sub> transition of DOCO<sup>+</sup> near 100.4 GHz in emission with the IRAM 30 m telescope. They viewed the detection as somewhat tentative because of issues in the laboratory rest frequencies which have been resolved in the meantime.\\
	+	At essentially the same time,\\
	+	A. Fuente, J. Cernicharo, E. Roueff, M. Gerin, J. Pety, N. Marcelino, R. Bachiller, B. Lefloch, O. Roncero, and A. Aguado,\\
	+	identified the same transition in B1b in the report on the\\
	+	[[https://doi.org/10.1051/0004-6361/201628285\|Ionization Fraction and the Enhanced Sulfur Chemistry in Barnard 1]]\\
	+	//Astron. Astrophys.//****, in press (2016),\\
	+	using the same telescope in an extensive molecular line survey.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 03, 2008; 03, 2012; 08, 2016
	+
	+	----
	+

hocs-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 25 Sep 2024 08:41:30 +0000

2024/04/17 12:13		current
Line 6:		Line 6:
	//Astrophys. J.// 965, Art. No. 149 (2024).\\		//Astrophys. J.// 965, Art. No. 149 (2024).\\
	The cation was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes. The transitions cover 34 to 161 GHz with //J"// = 2, 3, 6 − 13 and //K<sub>a</sub>// = 0. These //K<sub>a</sub>// = 0 are all considerably blended with //K<sub>a</sub>// = 0 lines of HNC<sup>34</sup>S because their //B + C// values are nearly identical. The contribution of HNC<sup>34</sup>S could be accounted for accurately through lines of HNCS, OCS, and OC<sup>34</sup>S and turned out to be less than that of HOCS<sup>+</sup>. Several lines are slightly or more severely blended in addition, but this is in most cases also well accounted. The cation is about a factor of 400 less abundant than OCS, about a factor of 7 less abundant than the isoelectronic HNCS, about a factor of 31 less abundant than the isovalent HOCO<sup>+</sup>, but at least more than a factor of 2 more abundant than the lower energy isomer HCSO<sup>+</sup>, which was not detected.\\		The cation was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes. The transitions cover 34 to 161 GHz with //J"// = 2, 3, 6 − 13 and //K<sub>a</sub>// = 0. These //K<sub>a</sub>// = 0 are all considerably blended with //K<sub>a</sub>// = 0 lines of HNC<sup>34</sup>S because their //B + C// values are nearly identical. The contribution of HNC<sup>34</sup>S could be accounted for accurately through lines of HNCS, OCS, and OC<sup>34</sup>S and turned out to be less than that of HOCS<sup>+</sup>. Several lines are slightly or more severely blended in addition, but this is in most cases also well accounted. The cation is about a factor of 400 less abundant than OCS, about a factor of 7 less abundant than the isoelectronic HNCS, about a factor of 31 less abundant than the isovalent HOCO<sup>+</sup>, but at least more than a factor of 2 more abundant than the lower energy isomer HCSO<sup>+</sup>, which was not detected.\\
		+	\\
		+
		+	V. Lattanzi, M. Sanz-Novo, V. M. Rivilla, M. Araki, H. A. Bunn, J. Martín-Pintado, I. Jiménez-Serra, and P. Caselli\\
		+	published more recently on\\
		+	[[https://doi.org/10.1051/0004-6361/202451518\|Advancing Spectroscopic Understanding of HOCS<sup>+</sup>: Laboratory Investigations and Astronomical Implications]]\\
		+	//Astron. Astrophys.// 689, Art. No. A260 (2024).\\
		+	After detection of HOCS<sup>+</sup> //a//-type transitions with //K<sub>a</sub>// > 0, it was possible to identify //K<sub>a</sub>// = 1 transitions in the line survey described above. Most of the transitions were heavily blended, but some were sufficiently clear.
	\\		\\

	----		----

-	Contributor(s): H. S. P. Müller; 04, 2024	+	Contributor(s): H. S. P. Müller; 04, 2024; 09, 2024

	----		----

hono

anonymous@undisclosed.example.com (Anonymous) — Fri, 29 Mar 2019 14:21:06 +0000

2019/03/29 15:19		current
Line 7:		Line 7:
	[[https://doi.org/10.1051/0004-6361/201935040\|The ALMA-PILS survey: First detection of nitrous acid (HONO) in the interstellar medium]]\\		[[https://doi.org/10.1051/0004-6361/201935040\|The ALMA-PILS survey: First detection of nitrous acid (HONO) in the interstellar medium]]\\
	//Astron. Astrophys.// 623 (2019), Art. No. L13.\\		//Astron. Astrophys.// 623 (2019), Art. No. L13.\\
-	15 lines, mostly between 329.5 and 362.4 GHz with 13 ≤ <i>J</i> ≤ 17 and <i>K<sub>a</sub></i> ≤ 6	+	15 lines, mostly between 329.5 and 362.4 GHz with 13 ≤ //J// ≤ 17 and //K<sub>a</sub>// ≤ 6
-	were detected with ALMA in emission toward the Solar-type protostar IRAS 162932422 B. The inferred rotational	+	were detected with ALMA in emission toward the Solar-type protostar IRAS 16293−2422 B. The inferred rotational
	temperature is about 100 K, and the NO/HONO ratio is about 22.		temperature is about 100 K, and the NO/HONO ratio is about 22.

hs2

anonymous@undisclosed.example.com (Anonymous) — Mon, 07 Jul 2025 14:06:21 +0000

2025/07/07 15:57		current
Line 10:		Line 10:
	More recently, G. Esplugues, M. Agúndez, G. Molpeceres, B. Tercero, C. Cabezas, N. Marcelino, R. Fuentetaja, and J. Cernicharo\\		More recently, G. Esplugues, M. Agúndez, G. Molpeceres, B. Tercero, C. Cabezas, N. Marcelino, R. Fuentetaja, and J. Cernicharo\\
	announced the\\		announced the\\
		+	[[https://doi.org/10.3847/2041-8213/aaa01b\|First Detection of HS<sub>2</sub> in a Cold Dark Cloud]],\\
		+	//Astron. Astrophys.// 699 L2 (2025).\\
		+	As usual, the authors rersorted to the QUIJOTE molecular line survey of TMC-1 carried out with the Yebes 40 m dish and covering 31.0 to 50.4 GHz.
		+	HS<sub>2</sub> is about 7 times more abundant than HSO in TMC-1.\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller; 12, 2017	+	Contributor(s): H. S. P. Müller; 12, 2017; 07, 2025

	----		----

hso

anonymous@undisclosed.example.com (Anonymous) — Tue, 27 Jun 2023 11:18:36 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Sulfeno, HSO, in the ISM =====
	+
	+	N. Marcelino, C. Puzzarini, M. Agúndez, R. Fuentetaja, B. Tercero, P. de Vicente, and J. Cernicharo\\
	+	described the\\
	+	[[https://doi.org/10.1051/0004-6361/202346935\|First Detection of the HSO Radical in Space]]\\
	+	//Astron. Astrophys.// 674, Art. No. L13 (2023).\\
	+	Several hyperfine components of the 1<sub>01</sub> − 0<sub>00</sub> transition near 39.5 and 39.9 GHz were detected with the Yebes 40 m dish toward the cold dense cores B1-b, TMC-1 CP, and L183 in the course of molecular line surveys. The strongest component near 39.532 GHz was also identified toward L483, L1495B, L1527, and Lupus-1A. The abundance ratio of SO to HSO shows some scatter, the former being often around a factor of 100 more abundant. There is indication that the ratio in L1527 is more like 6.\\
	+	\\
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2023
	+
	+	----

hydroxyaceton

anonymous@undisclosed.example.com (Anonymous) — Wed, 04 Mar 2026 10:30:13 +0000

2026/03/04 11:20		current
Line 8:		Line 8:
	\\		\\

-	M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, L. Colzi, S. Zeng, A. Megías, D. San Andrés, Á. López-Gallifa, A. Martínez-Henares, Z. T. P. Fried, B. A. McGuire, S. Martín, M. A. Requena-Torres, B. Tercero, P. de Vicente, L. Kolesniková, E. R. Alonso, E. J. Cocinero, J. C. Guillemin, and I. Kleiner\\
	In their work on\\		In their work on\\
	[[https://doi.org/10.1051/0004-6361/202558316\|Expanding the C3H6O2 Isomeric Interstellar Inventory: Discovery of Lactaldehyde and Methoxyacetaldehyde in G+0.693−0.027]]\\		[[https://doi.org/10.1051/0004-6361/202558316\|Expanding the C3H6O2 Isomeric Interstellar Inventory: Discovery of Lactaldehyde and Methoxyacetaldehyde in G+0.693−0.027]]\\
	//Astron. Astrophys.// 706, (2026) Art. No. A316.\\		//Astron. Astrophys.// 706, (2026) Art. No. A316.\\
	M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, L. Colzi, S. Zeng, A. Megías, D. San Andrés, Á. López-Gallifa, A. Martínez-Henares, Z. T. P. Fried, B. A. McGuire, S. Martín, M. A. Requena-Torres, B. Tercero, P. de Vicente, L. Kolesniková, E. R. Alonso, E. J. Cocinero, J. C. Guillemin, and I. Kleiner\\		M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, L. Colzi, S. Zeng, A. Megías, D. San Andrés, Á. López-Gallifa, A. Martínez-Henares, Z. T. P. Fried, B. A. McGuire, S. Martín, M. A. Requena-Torres, B. Tercero, P. de Vicente, L. Kolesniková, E. R. Alonso, E. J. Cocinero, J. C. Guillemin, and I. Kleiner\\
-	also report the detection of hydroxypropanone, also known as Hydroxyacetone toward	+	also report the detection of hydroxypropanone, also known as hydroxyacetone, in the course of a molecular line survey of this cold, shocked molecular cloud near Sagittarius B2 and in the Galactic center region. Several transitions with good signal-to-noise ratio (S/N) between 32 and 102 GHz were (essentially) unblended. The authors provide column density raios of the C<sub>3</sub>H<sub>6</sub>O<sub>2</sub> isomers.\\
-	.\\	+
	\\		\\

hydroxymethylium

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:15:32 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The detection of hydroxymethylium, H2COH+, in the ISM =====
	+
	+	Hydroxymethylium, also known os protonated formaldehyd, was detected toward Sgr B2(M) and (N), Orion KL, W51, and possibly in NGC 7538 and DR21(OH). It was not found toward several dark clouds. The account was reported by\\
	+	M. Ohishi, S. Ishikawa, T. Amano, H. Oka, W. M. Irvine, J. E. Dickens, L. M. Ziurys, and A. J. Apponi,\\
	+	[[https://doi.org/10.1086/310325\|Detection of a New Interstellar Molecular Ion, H<sub>2</sub>COH<sup>+</sup> (Protonated Formaldehyde)]]\\
	+	//Astrophys. J.// 471, L61–L64 (1996).\\
	+	Altogether, six transitions were observed between 31 and 174 GHz using the Nobeyama 45 m dish and the Kitt Peak 12 m dish.
	+
	+	A. Bacmann, E. García-García, and A. Faure,\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201628280\|Detection of Protonated Formaldehyde in the Prestellar Core L1689B]]\\
	+	//Astron. Astrophys.// 588, Art. No. L8 (2016).\\
	+	The authors used the IRAM 30 m telescope to search for four transitions between 102 and 169 GHz. Three lower energy transitions were detected, the higher lying transition near 102 GHz was within the noise level, in agreement with a rotational temperature of about 10 K.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2006; 04, 2016
	+
	+	----
	+

hydroxypropenal

anonymous@undisclosed.example.com (Anonymous) — Thu, 15 Aug 2024 17:25:16 +0000

2024/08/15 19:17		current
Line 12:		Line 12:
	[[https://doi.org/10.1051/0004-6361/202450029\|The rotation-tunneling spectrum of 3-hydroxypropenal and confirmation of its detection toward IRAS 16293−2422 B]]\\		[[https://doi.org/10.1051/0004-6361/202450029\|The rotation-tunneling spectrum of 3-hydroxypropenal and confirmation of its detection toward IRAS 16293−2422 B]]\\
	//Astron. Astrophys.// 687 (2024), Art. No. A8.\\		//Astron. Astrophys.// 687 (2024), Art. No. A8.\\
-	The authors reported a very extensive line list from new (sub-) millimeter spectroscopic measurements. They were able to constrain the rotational temperature to 125 K. No additional lines were identified in the PILS data, but 7 additional lines were identified in archival ALMA data of the same source and with a similar spatial resolution. The detection is now certainly beyond any doubt.\\	+	The authors reported a very extensive line list from new (sub-) millimeter spectroscopic measurements. They were able to constrain the rotational temperature to 125 K. No additional lines were identified in the PILS data, but 7 additional lines were identified in archival ALMA data of the same source and with a similar spatial resolution. The column density is roughly a factor of 2.2 lower than that of propanal, a factor of about 42 lower than that of propene, and about a factor of 3 higher than that of propenal. The detection is now certainly beyond any doubt.\\
	\\		\\

iminopropin

anonymous@undisclosed.example.com (Anonymous) — Mon, 24 Aug 2020 08:52:13 +0000

2020/08/21 14:38		current
Line 1:		Line 1:
	===== Iminopropyne, HCCCHNH, in the Interstellar Medium =====		===== Iminopropyne, HCCCHNH, in the Interstellar Medium =====

-	L. Bizzocchi, D. Prudenzano, V. M. Rivilla, A. Pietropolli-Charmet, B. M. Giuliano, P. Caselli, J. Martín-Pintado, I. Jiménez-Serra, S. Martín, M. A. Requena-Torres, F. Rico-Villas, S. Zeng and J.-C. Guillemin\\	+	L. Bizzocchi, D. Prudenzano, V. M. Rivilla, A. Pietropolli-Charmet, B. M. Giuliano, P. Caselli, J. Martín-Pintado, I. Jiménez-Serra, S. Martín, M. A. Requena-Torres, F. Rico-Villas, S. Zeng, and J.-C. Guillemin\\
	reported on\\		reported on\\
-	**[[https://doi.org/10.1051/0004-6361/202038083\|Propargylimine in the Laboratory and in Space: Millimetre-wave	+	[[https://doi.org/10.1051/0004-6361/202038083\|Propargylimine in the Laboratory and in Space: Millimetre-wave Spectroscopy and its First Detection in the ISM]]\\
-	Spectroscopy and its First Detection in the ISM]]**\\	+
	//Astron. Astrophys.// 628, Art. No. A10 (2019).\\		//Astron. Astrophys.// 628, Art. No. A10 (2019).\\
	A total of 18 rotational transitions of the lower energy //Z//-conformer of iminopropyne, also known as propargylamine, were detected in the course of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), with the IRAM 30 m dish at 3 and 2 mm. Several lines, however, are severely blended, but about one third are not or only somewhat blended. The inferred rotational temperature of 8 K is a value typical for dark clouds. It explains the non-detection of the slightly higher lying //E//-conformer. The column density is about a factor of 4 lower than vinyl cyanide, a tautomer of iminopropyne.		A total of 18 rotational transitions of the lower energy //Z//-conformer of iminopropyne, also known as propargylamine, were detected in the course of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), with the IRAM 30 m dish at 3 and 2 mm. Several lines, however, are severely blended, but about one third are not or only somewhat blended. The inferred rotational temperature of 8 K is a value typical for dark clouds. It explains the non-detection of the slightly higher lying //E//-conformer. The column density is about a factor of 4 lower than vinyl cyanide, a tautomer of iminopropyne.

inden

anonymous@undisclosed.example.com (Anonymous) — Thu, 27 May 2021 09:14:04 +0000

2021/05/27 11:11		current
Line 9:		Line 9:
	A. M. Burkhardt, K. L. K. Lee, P. B. Changala, C. N. Shingledecker, I. R. Cooke, R. A. Loomis, H. Wei, S. B. Charnley, E. Herbst, M. C. McCarthy, and B. A. McGuire\\		A. M. Burkhardt, K. L. K. Lee, P. B. Changala, C. N. Shingledecker, I. R. Cooke, R. A. Loomis, H. Wei, S. B. Charnley, E. Herbst, M. C. McCarthy, and B. A. McGuire\\
	submitted a report somewhat earlier but that appeared later on the\\		submitted a report somewhat earlier but that appeared later on the\\
-	[[https://arxiv.org/abs/2104.15117\|Discovery of the pure polycyclic aromatic hydrocarbon indene (//c//-C<sub>9</sub>H<sub>8</sub>) with GOTHAM observations of TMC-1]]\\	+	[[https://doi.org/10.3847/2041-8213/abfd3a\|Discovery of the pure polycyclic aromatic hydrocarbon indene (//c//-C<sub>9</sub>H<sub>8</sub>) with GOTHAM observations of TMC-1]]\\
-	//Astrophys. J. Lett.// , (2021), in press.\\	+	//Astrophys. J. Lett.// **913, Art. No. L18** (2021).\\
-	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure . No individual lines were detected, as usually in this survey. Stacking of all lines of all four major velocity components, however, yielded a signal slighly above 5σ. Note, however, that this method becomes questionable with weak lines as those of indene. As can be seen in Fig. 4 of the previous paper, TMC-1 is not line poor anymore at 1 cm wavelength on the level of the indene lines; the situation may be slightly better at longer wavelengths.	+	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure . No individual lines were detected, as usually in this survey. Stacking of all lines of all four major velocity components, however, yielded a signal slighly above 5σ. Note, however, that this method becomes questionable with weak lines as those of indene. As can be seen in Fig. 4 of the previous paper, TMC-1 is not line poor anymore at 1 cm wavelength on the level of the indene lines; the situation may be slightly better at longer wavelengths. The derived column densities of the two reports agree.\\

isobuten

anonymous@undisclosed.example.com (Anonymous) — Mon, 04 Dec 2023 12:17:34 +0000

2023/12/04 13:00		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202347112\|Millimetre and Submillimetre Spectroscopy of Isobutene and Its Detection in the Molecular Cloud G+0.693]]\\		[[https://doi.org/10.1051/0004-6361/202347112\|Millimetre and Submillimetre Spectroscopy of Isobutene and Its Detection in the Molecular Cloud G+0.693]]\\
	//Astron. Astrophys.// 680, Art. No. A25 (2023).\\		//Astron. Astrophys.// 680, Art. No. A25 (2023).\\
-	Isobutene, (CH<sub>3</sub>)<sub>2</sub>C=CH<sub>2</sub>, is one of four non-cyclic C<sub>4</sub>H<sub>8</sub> isomers; another isomer is cyclobutane. \\	+	Isobutene, (CH<sub>3</sub>)<sub>2</sub>C=CH<sub>2</sub>, is one of four non-cyclic C<sub>4</sub>H<sub>8</sub> isomers; another isomer is cyclobutane. It was identified in the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes. Six //b//-type lines with 3 ≤ //J// ≤ 10, //K<sub>c</sub>// between //J// and //J// − 2, and with unresolved internal rotation splitting were not or only slightly blended and show reasonable signal-to-noise ratios. The authors also identify propene in this source. Both molecules have excitation temperatures of about 15 K, and propene has an about three times higher column density than isobutene. Isobutene is only the second molecules with a branched carbon chain after isopropyl cyanide.\\
	\\		\\

l-c3h

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 14:36:42 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Propynylidyne, l-C3H, in Space =====
	+
	+	C<sub>3</sub>H exists in two isomeric forms, a linear one and a cyclic one. The latter is considerably higher in energy. Still, both seem to be equally abundant in cold dark clouds. //l//-C<sub>3</sub>H was detected first toward the dense cold molecular cloud TMC-1 and in the circumstellar envelope of the carbon-rich AGB star CW Leo, aka IRC +10216, by\\
	+	P. Thaddeus, C. A. Gottlieb, Å. Hjalmarson, L. E. B. Johansson, W. M. Irvine, P. Friberg, and R. A. Linke,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1985ApJ...294L..49T\|Astronomical Identification of the C<sub>3</sub>H Radical]],\\
	+	//Astrophys. J.// 294, L49–L53 (1985).\\
	+	Four hfs components of the //J// = 3/2 – 1/2 transition near 32.6 GHz in the lower lying <sup>2</sup>Π<sub>1/2</sub> fine structure ladder were detected with the Onsala 20 m telescope. 2 parity split lines each were detected with several telescopes toward CW Leo for the 7/2 – 5/2, 9/2 – 7/2, and 13/2 – 11/2 transitions of the <sup>2</sup>Π<sub>1/2</sub> ladder near 76.2, 98.0, and 141.7 GHz as well as the 9/2 – 7/2 transitions of the <sup>2</sup>Π<sub>3/2</sub> ladder near 103.3 GHz.
	+
	+	The radical was also observed in three translucent molecular clouds CB 17, CB 24, and CB 228 by\\
	+	B. E. Turner, E. Herbst, and R. Terzieva,\\
	+	[[https://doi.org/10.1086/313301\|The Physics and Chemistry of Small Translucent Molecular Clouds. XIII. The Basic Hydrocarbon Chemistry]],\\
	+	//Astrophys. J. Suppl. Ser.// 126, 427–460 (2000).
	+
	+	The higher lying (CCH) bending mode is subjected to very strong Renner-Teller interaction causing one of the Σ components to be only 27.2 cm<sup>–1</sup> (39.1 K) above ground. Transitions within this state were observed in the circumstellar envelope of the carbon rich late type star CW Leo by\\
	+	J.Cernicharo, M. Guélin, and C. Kahane,\\
	+	[[https://doi.org/10.1051/aas:2000147\|A λ 2 mm Molecular Line Survey of the C-star Envelope IRC+10216]],\\
	+	//Astron. Astrophys. Suppl. Ser.// 142, 181–215 (2000).
	+
	+	Propynylidyne was also detected in the circumstellar envelope of the post-AGB object (protoplanetary nebula) V353 Aur by\\
	+	J. R. Pardo and J. Cernicharo,\\
	+	[[https://ui.adsabs.harvard.edu/abs/2007ApJ...654..978P\|Molecular Abundances in CRL 618]],\\
	+	//Astrophys. J.// 654, 978–987 (2007).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 09, 2011
	+
	+	----
	+

l-c3h2

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 14:58:55 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Propadienylidene, l-C3H2, in Space =====
	+
	+	Propadienylidene is a higher energy isomer of the earlier detected, rather ubiquitous cyclopropenylidene.\\
	+	J. Cernicharo, C. A. Gottlieb, M Guélin, T. C. Killian, G. Paubert, P. Thaddeus, and J. M. Vrtilek,\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1991ApJ...368L..39C\|Astronomical Detection of H<sub>2</sub>CCC]],\\
	+	//Astrophys. J.// 368, L39–L41 (1991)\\
	+	The //para// ground state transition 1<sub>0,1</sub> – 0<sub>0,0</sub> near 20.8 GHz was detected with the Effelsberg 100 m telescope in emission together with the //ortho// transitions 5<sub>1,5</sub> – 4<sub>1,4</sub>, 5<sub>1,4</sub> – 4<sub>1,3</sub>, and 7<sub>1,6</sub> – 6<sub>1,5</sub> near 103.0, 104.9, and 146.9 GHz, respectively. These transitions were made with the IRAM 30 m telescope. The molecule may have been detected also in the circumstellar envelope of CW Leonis, also known as IRC +10216.
	+
	+	J. Cernicharo, P. Cox, D. Fossé and R. Güsten,\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1999A%26A...351..341C\|Detection of Linear C<sub>3</sub>H<sub>2</sub> in Absorption toward Continuum Sources]],\\
	+	//Astron. Astrophys.// 351, 341–346 (1999)\\
	+	The 1<sub>0,1</sub> – 0<sub>0,0</sub> transition was observed in absorption toward the continuum sources W49, W51e1/e2 and W51D.
	+
	+	The Molecule was also deteceted in a source of Warm Carbon Chain Chemistry by\\
	+	N. Sakai, T. Sakai, T. Hirota, and S. Yamamoto,\\
	+	[[https://doi.org/10.1051/0004-6361/201424568\|Abundant Carbon-Chain Molecules toward the Low-Mass Protostar IRAS 04368+2557 in L1527]],\\
	+	//Astrophys. J.// 672, 371–381 (2008)
	+
	+	The Molecule was also deteceted in the CO<sup>+</sup> peak of the Orion Bar photodissociation regions by\\
	+	S. Cuadrado, J. R. Goicoechea, P. Piller, J. Cernicharo, A. Fuente, and C. Joblin,\\
	+	[[https://doi.org/10.1051/0004-6361/201424568\|The Chemistry and Spatial Distribution of Small Hydrocarbons in UV-irradiated Molecular Clouds: the Orion Bar PDR]],\\
	+	//Astron. Astrophys.// 575, Art. No. A82 (2015)
	+
	+	S. Spezzano, H. Gupta, S. Brünken, C. A. Gottlieb, P. Caselli, K. M. Menten, H. S. P. Müller, L. Bizzocchi, P. Schilke, M. C. McCarthy, and S. Schlemmer,\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201527460\|A Study of the C<sub>3</sub>H<sub>2</sub> Isomers and Isotopologues: First Interstellar Detection of HDCCC]],\\
	+	//Astron. Astrophys.// 575, Art. No. A110 (2016)\\
	+	The 5<sub>0,5</sub> – 4<sub>0,4</sub> transition near 96.9 GHz was detected with the IRAM 30 m telescope in emission toward the starless cores TMC-1C and L1544. In addition, the 1<sub>0,1</sub> – 0<sub>0,0</sub> transition near 19.4 GHz was detected in TMC-1 with the 100 m GBT.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 02, 2016
	+
	+	----
	+

l-c4h2

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 19:58:41 +0000

l-h2c3o

anonymous@undisclosed.example.com (Anonymous) — Tue, 03 Feb 2026 13:29:14 +0000

2026/02/03 12:15		current
Line 3:		Line 3:
	G. Esplugues, J. C. Loison, M. Agúndez, G. Molpeceres, N. Marcelino, B. Tercero, and J. Cernicharo\\		G. Esplugues, J. C. Loison, M. Agúndez, G. Molpeceres, N. Marcelino, B. Tercero, and J. Cernicharo\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1051/0004-6361/202557355\|Discovery of Linear Propadienone — Study of the Cof linear and Cyclic H2C3O and H2C3S in TMC-1]]\\	+	[[https://doi.org/10.1051/0004-6361/202557355\|Discovery of Linear Propadienone — Study of the Chemistry of Linear and Cyclic H2C3O and H2C3S in TMC-1]]\\
	//Astron. Astrophys.// 705, Art. No. A206 (2026).\\		//Astron. Astrophys.// 705, Art. No. A206 (2026).\\
-	The elusive propadienone was detected in two //a//-type transitions with //K<sub>a</sub>// = 0 and //J// = 4 − 3 and 5 − 4 near 34.6 and 43.2 GHz in the course of a molecular line survey in the 31.0 to 50.3 GHz region carried out with the 40 m Yebes telescope. The very small tunneling splitting of ~45 kHz was not resolved. The identification of two transitions can be considered as quite secure in TMC-1. Assuming a rotational temperature of 4.8 K, taken from the isomeric //ortho//-cyclopropenone, a cyclopropenone to propadienone ratio of about 9 was derived.\\	+	The elusive propadienone was detected in two //a//-type transitions with //K<sub>a</sub>// = 0 and //J// = 4 − 3 and 5 − 4 near 34.6 and 43.2 GHz in the course of a molecular line survey in the 31.0 to 50.3 GHz region carried out with the 40 m Yebes telescope. The very small tunneling splitting of ~45 kHz was not resolved. The identification of two transitions can be considered as quite secure in TMC-1. Assuming a rotational temperature of 4.8 K, taken from the isomeric //ortho//-cyclopropenone, a cyclopropenone to propadienone ratio of about 9 was derived, while the propynal to propadienone ratio is roughly 23.\\
	\\		\\

main_alt

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Feb 2019 21:38:46 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	====== Molecules in Space (as of 10/2002) ======
	+
	+	=== 2-7 atoms 8-13 atoms ===
	+
	+	Note: Deuterium isotopomers are given seperately only if their method of detection is intrinsically different from that of pure hydrogen isotopomers.\\
	+
	+
	+	All molecules have been detected (also) by rotational spectroscopy in the radiofrequency to far-infrared regions unless indicated otherwise.\\
	+	* indicates molecules that can be detected by their rotation-vibration spectrum,\\
	+	%%**%% those detected by electronic spectroscopy only.\\
	+	Transition metal molecules detected in atmospheres of stars by electronic spectroscopy are currently not included. Tentative detections are indicated by "?". These include molecules for which (partial) overlap of lines cannot be ruled at the moment.\\
	+
	+
	+	We welcome comments on this list !\\
	+
	+
	+	^2 atoms ^3 atoms ^4 atoms ^5 atoms ^6 atoms ^7 atoms ^
	+	\|H<sub>2</sub> \|C<sub>3</sub>* \|c-C<sub>3</sub>H \|C<sub>5</sub>* \|C<sub>5</sub>H \|C<sub>6</sub>H \|
	+	\|AlF \|C<sub>2</sub>H \|l-C<sub>3</sub>H \|C<sub>4</sub>H \|l-H<sub>2</sub>C<sub>4</sub>\|CH<sub>2</sub>CHCN \|
	+	\|AlCl \|C<sub>2</sub>O \|C<sub>3</sub>N \|C<sub>4</sub>Si \|C<sub>2</sub>H<sub>4</sub>* \|CH<sub>3</sub>C<sub>2</sub>H \|
	+	\|C<sub>2</sub>%%**%% \|C<sub>2</sub>S \|C<sub>3</sub>O \|l-C<sub>3</sub>H<sub>2</sub>\|CH<sub>3</sub>CN \|HC<sub>5</sub>N \|
	+	\|CH \|CH<sub>2</sub> \|C<sub>3</sub>S \|c-C<sub>3</sub>H<sub>2</sub>\|CH<sub>3</sub>NC \|HCOCH<sub>3</sub> \|
	+	\|[[CH+.html\|CH<sup>+</sup>]] \|HCN \|C<sub>2</sub>H<sub>2</sub>* \|CH<sub>2</sub>CN \|CH<sub>3</sub>OH \|NH<sub>2</sub>CH<sub>3</sub> \|
	+	\|CN \|HCO \|CH2D<sup>+</sup>? \|CH<sub>4</sub>* \|CH<sub>3</sub>SH \|c-C<sub>2</sub>H<sub>4</sub>O \|
	+	\|CO \|HCO<sup>+</sup> \|HCCN \|HC<sub>3</sub>N \|HC<sub>3</sub>NH<sup>+</sup>\|[[http://www.aoc.nrao.edu/pr/vinylalco.html\|H<sub>2</sub>CCHOH]]\|
	+	\|CO<sup>+</sup> \|HCS<sup>+</sup> \|HCNH<sup>+</sup> \|HC<sub>2</sub>NC \|HC<sub>2</sub>CHO \| \|
	+	\|CP \|HOC<sup>+</sup> \|HNCO \|[[Formic_Acid.html\|HCOOH]] \|NH<sub>2</sub>CHO \| \|
	+	\|CSi \|H<sub>2</sub>O \|HNCS \|H<sub>2</sub>CHN \|C<sub>5</sub>N \| \|
	+	\|HCl \|H<sub>2</sub>S \|HOCO<sup>+</sup> \|H<sub>2</sub>C<sub>2</sub>O \|l-HC<sub>4</sub>H* \| \|
	+	\|KCl \|HNC \|H<sub>2</sub>CO \|H<sub>2</sub>NCN \| \| \|
	+	\|NH%%**%% \|HNO \|H<sub>2</sub>CN \|HNC<sub>3</sub> \| \| \|
	+	\|NO \|MgCN \|H<sub>2</sub>CS \|SiH<sub>4</sub>* \| \| \|
	+	\|NS \|MgNC \|H<sub>3</sub>O<sup>+</sup> \|H<sub>2</sub>COH<sup>+</sup>\| \| \|
	+	\|NaCl \|N<sub>2</sub>H<sup>+</sup> \|NH<sub>3</sub> \| \| \| \|
	+	\|OH \|N<sub>2</sub>O \|c-SiC<sub>3</sub> \| \| \| \|
	+	\|PN \|NaCN \|CH<sub>3</sub>* \| \| \| \|
	+	\|SO \|OCS \| \| \| \| \|
	+	\|SO<sup>+</sup> \|SO<sub>2</sub> \| \| \| \| \|
	+	\|SiN \|c-SiC2 \| \| \| \| \|
	+	\|SiO \|CO<sub>2</sub>* \| \| \| \| \|
	+	\|SiS \|NH<sub>2</sub> \| \| \| \| \|
	+	\|CS \|H<sub>3</sub><sup>+</sup> \| \| \| \| \|
	+	\|HF \|H<sub>2</sub>D<sup>+</sup> \| \| \| \| \|
	+	\|SH* \|SiCN \| \| \| \| \|
	+	\|HD \|[[http://www.journals.uchicago.edu/ApJ/journal/issues/ApJL/v564n1/15690/brief/15690.abstract.html\|AlNC]]\| \| \| \| \|
	+	\|[[http://www.journals.uchicago.edu/ApJ/journal/issues/ApJL/v566n2/16003/brief/16003.abstract.html\|FeO]] \| \| \| \| \| \|
	+	\|[[http://www.journals.uchicago.edu/ApJ/journal/issues/ApJ/v576n2/55626/brief/55626.abstract.html\|O<sub>2</sub>]]?\| \| \| \| \| \|
	+	\|8 atoms \|9 atoms \|10 atoms \|11 atoms \|12 atoms \|13 atoms \|
	+	\|CH<sub>3</sub>C<sub>3</sub>N \|CH<sub>3</sub>C<sub>4</sub>H \|CH<sub>3</sub>C<sub>5</sub>N ? \|HC<sub>9</sub>N \|C<sub>6</sub>H<sub>6</sub>* \|HC<sub>11</sub>N \|
	+	\|HCOOCH<sub>3</sub> \|CH<sub>3</sub>CH<sub>2</sub>CN \|(CH<sub>3</sub>)<sub>2</sub>CO \| \| \| \|
	+	\|[[HAc.html\|CH<sub>3</sub>COOH]] \|(CH<sub>3</sub>)<sub>2</sub>O \|(CH<sub>2</sub>OH)<sub>2</sub>?\| \| \| \|
	+	\|C<sub>7</sub>H \|CH<sub>3</sub>CH<sub>2</sub>OH \| \| \| \| \|
	+	\|H<sub>2</sub>C<sub>6</sub> \|HC<sub>7</sub>N \| \| \| \| \|
	+	\|CH<sub>2</sub>OHCHO? \|C<sub>8</sub>H \| \| \| \| \|
	+	\|l-HC<sub>6</sub>H* \| \| \| \| \| \|
	+
	+
	+	----
	+
	+	You are visitor No. {{http://www.uni-koeln.de/cgi-bin/count3.gif/spekmolecules?44x10}}
	+
	+
	+	----
	+

me

anonymous@undisclosed.example.com (Anonymous) — Wed, 12 Nov 2025 14:03:51 +0000

2025/11/12 14:54		current
Line 12:		Line 12:
	[[https://doi.org/10.3847/2041-8213/ae0e6b\|A Quest for Sulfur-bearing Refractory Species: Identification of CaS in the Interstellar Medium]]\\		[[https://doi.org/10.3847/2041-8213/ae0e6b\|A Quest for Sulfur-bearing Refractory Species: Identification of CaS in the Interstellar Medium]]\\
	//Astrophys. J. Lett.// 993, Art. No. L42 (2025).\\		//Astrophys. J. Lett.// 993, Art. No. L42 (2025).\\
-	Four transitions with //J// = 19 − 18 or 18 − 17 and //v// = 0 or 1 were observed with ALMA toward the G351.77-mm1 protostellar disk. Three lines are blended, but the one with //J// = 19 − 18 and //v// = 0 at 200.714 GHz is partially clear and the //J// = 18 − 17 and //v// = 1 at 189.261 GHz apparently helps to constrain //T//<sub>rot</sub> and the column density. //J// = 22 − 21	+	Four transitions with //J// = 19 − 18 or 18 − 17 and //v// = 0 or 1 were observed with ALMA toward the G351.77-mm1 protostellar disk. Three lines are blended, but the one with //J// = 19 − 18 and //v// = 0 at 200.714 GHz is partially clear and the //J// = 18 − 17 and //v// = 1 at 189.261 GHz apparently helps to constrain //T//<sub>rot</sub> and the column density. //J// = 22 − 21, //v// = 0, at 232.372 GHz was covered by archival ALMA data, and the high-resolution recording suggests this line dominates at least part of the emission feature. The same extent as NaCl and the value of //T//<sub>rot</sub> can be viewed in support of the assignment to CaS. Slight caution may be advised nevertheless until further lines will have been detected.
	\\		\\

Line 23:		Line 23:

	----		----
-
-

meac

anonymous@undisclosed.example.com (Anonymous) — Wed, 24 Apr 2019 14:12:11 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Methyl Acetate, CH3OC(O)CH3, in Orion KL =====
	+
	+	B. Tercero, I. Kleiner, J. Cernicharo, H. V. L. Nguyen, A. López, and G. M. Muñoz Caro\\
	+	recently reported on the\\
	+	[[https://doi.org/10.1088/2041-8205/770/1/L13\|Discovery of Methyl Acetate and Gauche Ethyl Formate in Orion]]\\
	+	//Astrophys. J.// 770, (2013) Art. No. L13.\\
	+	The detection was made in the course of a molecular line survey carried out with the IRAM 30 m radio telescope. At a rotational temperature of about 150 K, very many transitions of methyl acetate have non-negligible intensities. However, many of them are blended severely with emissions of other molecules. Nevertheless, a considerable number of transitions are not or only slightly blended, such that its detection can be considered secure in spite of many still unassigned lines. Its column density is about a factor of five higher than that derived for ethyl formate in this source.
	+
	+	Methyl acetate is the third ester and the first acetate to be detected in the ISM after [[molecules:ism:methylformiat\|methyl formate]] and [[molecules:ism:ethylformiat\|ethyl formate]]. It is an isomer of ethyl formate.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 07, 2013
	+
	+
	+	----
	+

mec3n

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Jun 2021 13:19:21 +0000

2021/06/22 15:15		current
Line 8:		Line 8:

	C. Cabezas, E. Roueff, B. Tercero, M. Agúndez, N. Marcelino, P. de Vicente, and J. Cernicharo\\		C. Cabezas, E. Roueff, B. Tercero, M. Agúndez, N. Marcelino, P. de Vicente, and J. Cernicharo\\
-	reported on\\	+	reported on the\\
	[[https://doi.org/10.1051/0004-6361/202141371\|Detection of deuterated methylcyanoacetylene, CH<sub>2</sub>DC<sub>3</sub>N, in TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202141371\|Detection of deuterated methylcyanoacetylene, CH<sub>2</sub>DC<sub>3</sub>N, in TMC-1]]\\
	//Astron. Astrophys.// 650, Art. No. L15 (2021).\\		//Astron. Astrophys.// 650, Art. No. L15 (2021).\\
-	The molecule was identified through 15 //a//-type transitions with 7 ≤ //J// ≤ 12 and //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. A value of //T//<sub>rot</sub> = 5.0 ± 0.5 K was derived. The column density of butenyne is about a factor of 1.8 higher than that of the isoelectronic vinyl cyanide.\\	+	The molecule was identified through 15 //a//-type transitions with 7 ≤ //J// ≤ 12 and //K<sub>a</sub>// = 0 and 1 in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz. A value of //T//<sub>rot</sub> = 8.0 ± 0.5 K was derived. The column density of monodeuterated methylcyanoacetylene is about a factor of 22 lower than that of the fully hydrogenated isotopolog; thus the H/D ratio per H atom is about 66.\\

mec5n

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:51:57 +0000

2019/02/25 22:38		current
Line 3:		Line 3:
	Cyanopentadiyne, CH<sub>3</sub>C<sub>5</sub>N, also known as methylcyanodiacetylene, has been detected first by:\\		Cyanopentadiyne, CH<sub>3</sub>C<sub>5</sub>N, also known as methylcyanodiacetylene, has been detected first by:\\
	L. E. Snyder, T. L. Wilson, C. Henkel, P. R. Jewell, and C. M. Walmsley,\\		L. E. Snyder, T. L. Wilson, C. Henkel, P. R. Jewell, and C. M. Walmsley,\\
-	[[http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?bibcode=1984BAAS...16Q.959S\|Detection of Interstellar Methylcyanodiacetylene in the Dark Dust Cloud TMC 1]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1984BAAS...16Q.959S\|Detection of Interstellar Methylcyanodiacetylene in the Dark Dust Cloud TMC 1]]\\
-	//Bull. Am. Atron. Soc.// 16, 959 (1984).\\	+	//Bull. Am. Astron. Soc.// 16, 959 (1984).\\
	Only three lines were detected, of which one apparently was blended. Therefore, this detection was deemed tentative.		Only three lines were detected, of which one apparently was blended. Therefore, this detection was deemed tentative.

	More recently, the 100 m GBT was used to detect the //J// = 12 – 11 to 16 – 15 transitions with //K// = 0 and 1 between 18.6 and 24.9 GHz in emission, also toward TMC-1, by\\		More recently, the 100 m GBT was used to detect the //J// = 12 – 11 to 16 – 15 transitions with //K// = 0 and 1 between 18.6 and 24.9 GHz in emission, also toward TMC-1, by\\
	L. E. Snyder, J. M. Hollis, P. R. Jewell, F. J. Lovas, and A. Remijan,\\		L. E. Snyder, J. M. Hollis, P. R. Jewell, F. J. Lovas, and A. Remijan,\\
-	[[http://dx.doi.org/10.1086/505323\|Confirmation of Interstellar Methylcyanodiacetylene]];\\	+	[[https://doi.org/10.1086/505323\|Confirmation of Interstellar Methylcyanodiacetylene]];\\
	//Astrophys. J.// 647, 412–417 (2006).		//Astrophys. J.// 647, 412–417 (2006).

Line 16:		Line 16:

	Contributor(s): H. S. P. Müller; 09, 2005; 08, 2006; 08, 2012		Contributor(s): H. S. P. Müller; 09, 2005; 08, 2006; 08, 2012
-

	----		----

mec7n

anonymous@undisclosed.example.com (Anonymous) — Tue, 08 Mar 2022 14:27:06 +0000

2022/03/08 15:25		current
Line 5:		Line 5:
	[[https://doi.org/10.3847/1538-4357/ac3238\|CH3-Terminated Carbon Chains in the GOTHAM Survey of TMC-1: Evidence of Interstellar CH<sub>3</sub>C<sub>7</sub>N]]\\		[[https://doi.org/10.3847/1538-4357/ac3238\|CH3-Terminated Carbon Chains in the GOTHAM Survey of TMC-1: Evidence of Interstellar CH<sub>3</sub>C<sub>7</sub>N]]\\
	//Astrophys. J.// 924 (2022), Art. No. 21.\\		//Astrophys. J.// 924 (2022), Art. No. 21.\\
-	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. Methylcyanotriacetylene was indentified through line-stacking with a signal-to-noise ratio that was slightly below the 5//σ// level deemed to be required for a secure detection, and thus viewed as a tentative detection. The derived low excitation temperature and the column density appear to be in line with trends from methylcyanoacetylene and methylcyanodiacetylene.\\	+	The observations were obtained in the course of the line survey Green Bank Telescope Observations of TMC-1: Hunting for Aromatic Molecules. The data were recorded with very high resolution which resolves, at least in part, the complex velocity structure and the <sup>14</sup>N hyperfine structure splitting. Methylcyanotriacetylene, aka cyanoheptatriyne, was indentified through line-stacking with a signal-to-noise ratio that was slightly below the 5//σ// level deemed to be required for a secure detection, and thus viewed as a tentative detection. The derived low excitation temperature and the column density appear to be in line with trends from methylcyanoacetylene and methylcyanodiacetylene.\\

mecho

anonymous@undisclosed.example.com (Anonymous) — Mon, 06 Mar 2023 12:09:16 +0000

2023/03/06 12:49		current
Line 52:		Line 52:
	species of acetaldehyde CH<sub>2</sub>DCOH and CH<sub>3</sub>COD]]**\\		species of acetaldehyde CH<sub>2</sub>DCOH and CH<sub>3</sub>COD]]**\\
	//Astron. Astrophys.// 624, Art. No. A70 (2019).\\		//Astron. Astrophys.// 624, Art. No. A70 (2019).\\
		+	The observations are based on PILS.\\
	\\		\\

-	J. Ferrer Asensio , S. Spezzano, L. H. Coudert, V. Lattanzi, C. P. Endres, J. K. Jørgensen, and P. Caselli\\	+	J. Ferrer Asensio, S. Spezzano, L. H. Coudert, V. Lattanzi, C. P. Endres, J. K. Jørgensen, and P. Caselli\\
-		+	described the\\
-		+	[[https://doi.org/10.1051/0004-6361/202245442\|Millimetre and Sub-millimetre Spectroscopy of Doubly Deuterated Acetaldehyde (CHD<sub>2</sub>CHO) and First Detection towards IRAS 16293−2422]]\\
		+	//Astron. Astrophys.// 670, Art. No. A177 (2023).\\
		+	The observations are based on PILS. The authors determine a CHD<sub>2</sub>CHO to CH<sub>2</sub>DCOH ratio of ~0.21. It is also worthwhile to compare the column densities with that of the main isotopic species. This translates to a deueration degree of ~0.017 per H atom for CH<sub>2</sub>DCOH and ~0.060 for CHD<sub>2</sub>CHO. Such enhancement in the degree of deueration in doubly or higher deuterated isotopologs compared with sinly deuterated variants has been found commonly.\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller; 11, 2009; 03, 2012; 01, 2014; 10, 2017; 01, 2019; 04, 2019	+	Contributor(s): H. S. P. Müller; 11, 2009; 03, 2012; 01, 2014; 10, 2017; 01, 2019; 04, 2019; 03, 2023.

	----		----

mecn

anonymous@undisclosed.example.com (Anonymous) — Wed, 03 Sep 2025 12:46:57 +0000

2019/10/23 21:59		current
Line 35:		Line 35:
	both <sup>13</sup>C species were detected by\\		both <sup>13</sup>C species were detected by\\
	E. C. Sutton, G. A. Blake, C. R. Masson, and T. G. Phillips,\\		E. C. Sutton, G. A. Blake, C. R. Masson, and T. G. Phillips,\\
-	[[http://cdsads.u-strasbg.fr/abs/1985ApJS...58..341S\|Molecular Line Survey of Orion A from 215 to 247 GHz]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1985ApJS...58..341S\|Molecular Line Survey of Orion A from 215 to 247 GHz]]\\
	//Astrophys. J. Suppl. Ser.// 58, 341–378 (1985).		//Astrophys. J. Suppl. Ser.// 58, 341–378 (1985).

Line 68:		Line 68:
	//Astrophys. J.// 274, 184–194 (1983).		//Astrophys. J.// 274, 184–194 (1983).

-	S. M. Fortman, J. P. McMillan, C. F.Neese, S. K. Randall, A. J. Remijan, T. L. Wilson, and F. C. De Lucia\\	+	S. M. Fortman, J. P. McMillan, C. F. Neese, S. K. Randall, A. J. Remijan, T. L. Wilson, and F. C. De Lucia\\
	gave a brief account on the detection of //v//<sub>8</sub> = 2 in their work\\		gave a brief account on the detection of //v//<sub>8</sub> = 2 in their work\\
	[[https://doi.org/10.1016/j.jms.2012.08.002\|An analysis of a preliminary ALMA Orion KL spectrum via the use of complete experimental spectra from the laboratory]]\\		[[https://doi.org/10.1016/j.jms.2012.08.002\|An analysis of a preliminary ALMA Orion KL spectrum via the use of complete experimental spectra from the laboratory]]\\
Line 77:		Line 77:
	[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\		[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\
	//Astron. Astrophys.// 559, Art. No. A47 (2013).\\		//Astron. Astrophys.// 559, Art. No. A47 (2013).\\
-	Besides observing these two lower lying vibrational states, they detected transitions pertaining to //v//<sub>4</sub> = 1, the next higher state, as well as transitions of the <sup>13</sup>C isotopologs in their //v//<sub>8</sub> = 1 vibrational states.	+	Besides observing these two lower lying vibrational states, they detected transitions pertaining to //v//<sub>4</sub> = 1, the next higher state, as well as transitions of the <sup>13</sup>C isotopologs in their //v//<sub>8</sub> = 1 vibrational states.\\
		+	\\

	----		----

menc

anonymous@undisclosed.example.com (Anonymous) — Tue, 26 Sep 2023 08:35:38 +0000

2023/09/26 10:33		current
Line 25:		Line 25:
	H. Calcutt, M. R. Fiechter, E. R. Willis, H. S. P. Müller, R. T. Garrod, J. K. Jørgensen, S. F. Wampfler, T. L. Bourke, A. Coutens, M. N. Drozdovskaya, N. F. W. Ligterink, and L. E. Kristensen,\\		H. Calcutt, M. R. Fiechter, E. R. Willis, H. S. P. Müller, R. T. Garrod, J. K. Jørgensen, S. F. Wampfler, T. L. Bourke, A. Coutens, M. N. Drozdovskaya, N. F. W. Ligterink, and L. E. Kristensen,\\
	reported on\\		reported on\\
-	[[https://doi.org/10.1051/0004-6361/201833140\|The ALMA-PILS survey: First detection of methyl isocyanide (CH<sub>3</sub>NC) in a solar-type protostar]]\\	+	[[https://doi.org/10.1051/0004-6361/201833140\|The ALMA-PILS survey: First detection of methyl isocyanide (CH<sub>3</sub>NC) in a solar-type protostar]]\\
-	//Astron. Astrophys.// ** (2018), in press**.\\	+	//Astron. Astrophys.// **617 (2018), Art. No. A95**.\\
	Several transitions with //J// = 17 – 16 and 18 – 17 and //K// between 0 and 7 were detected near 342 and 362 GHz, respectively toward source B. The molecule was not detected toward source A. The CH<sub>3</sub>CN to CH<sub>3</sub>NC ratio is about 200 toward source B and more than 5000 toward source A.\\		Several transitions with //J// = 17 – 16 and 18 – 17 and //K// between 0 and 7 were detected near 342 and 362 GHz, respectively toward source B. The molecule was not detected toward source A. The CH<sub>3</sub>CN to CH<sub>3</sub>NC ratio is about 200 toward source B and more than 5000 toward source A.\\
	\\		\\

menco

anonymous@undisclosed.example.com (Anonymous) — Mon, 06 Jul 2020 08:13:41 +0000

menh2

anonymous@undisclosed.example.com (Anonymous) — Tue, 05 Sep 2023 12:43:54 +0000

2023/03/06 14:45		current
Line 43:		Line 43:
	\\		\\

		+	P. Gyawali, R. A. Motiyenko, A. Belloche, I. Kleiner, V. V. Ilyushin, E. A. Alekseev, I. Gulaczyk and M. Kreglewski\\
		+	described the\\
		+	[[https://doi.org/10.1051/0004-6361/202346518\|Rotational Spectrum and Interstellar Detection of the First Torsionally Excited State of Methylamine]]\\
		+	//Astron. Astrophys.// 677, Art. No. A65 (2023).\\
		+	Five lines in //v//<sub>t</sub> = 1 were reported as blended or only slightly blended in addition to ten in //v//<sub>t</sub> = 0. The observational data are from the ReMoCA survey of Sagittarius B2(N) carried out with ALMA at 3 mm.\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller; 03, 2016; 06, 2019; 08, 2020; 03, 2023.	+	Contributor(s): H. S. P. Müller; 03, 2016; 06, 2019; 08, 2020; 03, 2023; 09, 2023.

	----		----

meo

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:19:40 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detection of the Methoxy Radical, CH3O, in the ISM =====
	+
	+	The methoxy radical, CH<sub>3</sub>O, is a symmetric top rotor with a doubly degenerate ground electronic state and large spin-orbit splitting. The Ω = 3/2 spin component (//J// = //N// + 1/2) is lower in energy than the 1/2 component. Λ-doubling can usually be resolved for //K// = 0, 1, and to some extent also for //K// = –1. Moreover, the molecule exhibts complex fine and hypperfine splitting. Seven stronger hyperfine components of the //N// = 1 – 0 (//F// = 2 – 1; Λ = –1 and +1 near 82.6 GHz) and //N// = 2 – 1 (both Λ components for each //F// = 4 – 3 and 3 – 2, and the –1 component for 2 – 1 near 137.5 GHz) were detected in emission with reasonable to good signal-to-noise ratio in the course of a 3 and 2 mm molecular line survey with the IRAM 30 m radiotelescope toward B1-b. Barnard 1 is a dark clould which is subjected to radiation or shocks.\\
	+	J. Cernicharo, N. Marcelino, E. Roueff, M. Gerin, A. Jiménez-Escobar, and G. M. Muñoz Caro,\\
	+	[[https://doi.org/10.1088/2041-8205/759/2/L43\|Discovery of the Methoxy Radical, CH<sub>3</sub>O, toward B1: Dust Grain and Gas-phase Chemistry in Cold Dark Clouds]]\\
	+	//Astrophys. J.// 759, Art. No. L43 (2012).
	+
	+	A. Bacmann and A. Faure\\
	+	investigated\\
	+	[[https://doi.org/10.1051/0004-6361/201526198\|The origin of gas-phase HCO and CH<sub>3</sub>O radicals in prestellar cores]]\\
	+	//Astron Astrophys.// 587, Art. No. A130 (2016).\\
	+	Transitions of the //N// = 1 – 0, Σ = +1 groups of lines were detected with the IRAM 30 m telecope in four of eight sources, L1495A-S, L1689B, L1709A, and TMC-2.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller 10, 2012; 02, 2016
	+
	+	----
	+

meoea

anonymous@undisclosed.example.com (Anonymous) — Wed, 04 Mar 2026 10:22:22 +0000

2026/03/04 11:08		current
Line 2:		Line 2:

	M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, L. Colzi, S. Zeng, A. Megías, D. San Andrés, Á. López-Gallifa, A. Martínez-Henares, Z. T. P. Fried, B. A. McGuire, S. Martín, M. A. Requena-Torres, B. Tercero, P. de Vicente, L. Kolesniková, E. R. Alonso, E. J. Cocinero, J. C. Guillemin, and I. Kleiner\\		M. Sanz-Novo, V. M. Rivilla, I. Jiménez-Serra, L. Colzi, S. Zeng, A. Megías, D. San Andrés, Á. López-Gallifa, A. Martínez-Henares, Z. T. P. Fried, B. A. McGuire, S. Martín, M. A. Requena-Torres, B. Tercero, P. de Vicente, L. Kolesniková, E. R. Alonso, E. J. Cocinero, J. C. Guillemin, and I. Kleiner\\
-	reported on the\\	+	reported on\\
	[[https://doi.org/10.1051/0004-6361/202558316\|Expanding the C3H6O2 Isomeric Interstellar Inventory: Discovery of Lactaldehyde and Methoxyacetaldehyde in G+0.693−0.027]]\\		[[https://doi.org/10.1051/0004-6361/202558316\|Expanding the C3H6O2 Isomeric Interstellar Inventory: Discovery of Lactaldehyde and Methoxyacetaldehyde in G+0.693−0.027]]\\
	//Astron. Astrophys.// 706, (2026) Art. No. A316.\\		//Astron. Astrophys.// 706, (2026) Art. No. A316.\\
-	Methoxyethanal, also known as methoxyacetaldehyde, was detected in the course of a molecular line survey of this cold, shocked molecular cloud near Sagittarius B2 and in the Galactic center region. Three transitions with good signal-to-noise ratio (S/N) between 35 and 50 GHz were essentially unblended, three further transitions were somewhat blended. \\	+	Methoxyethanal, also known as methoxyacetaldehyde, was detected in the course of a molecular line survey of this cold, shocked molecular cloud near Sagittarius B2 and in the Galactic center region. Three transitions with good signal-to-noise ratio (S/N) between 35 and 50 GHz were essentially unblended, three further transitions were somewhat blended. The authors provide column density raios of the C<sub>3</sub>H<sub>6</sub>O<sub>2</sub> isomers.\\
	\\		\\

meoh

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Feb 2019 21:38:46 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Methanol in Space =====
	+
	+	Methanol, CH<sub>3</sub>OH, also known as methyl alcohol, was among the early molecules to be detected in space. Its was first detected toward Sagittarius A and Sgr B2 in its //A// symmetry //a//-type //Q//-branch transition 1<sub>10</sub> – 1<sub>11</sub> near 834 MHz by:\\
	+	J. A. Ball, C. A. Gottlieb, A. E. Lilley, and H. E. Radford,\\
	+	[[http://dx.doi.org/10.1086/180654\|Detection of Methyl Alcohol in Sagittarius]]\\
	+	//Astrophys. J.// 162, L203–L210 (1970).
	+
	+	Soon thereafter, 5 subsequent //E// symmetry //Q//-branch transitions with 4 ≤ //J// ≤ 8 and //K// = +2 – +1 near 25 GHz were detected toward Orion A by:\\
	+	A. H. Barrett, P. R. Schwartz, and J. W. Waters,\\
	+	[[http://dx.doi.org/10.1086/180793\|]]\\
	+	//Astrophys. J.// 168, L101–L106 (1971).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 1, 2010
	+
	+
	+	----
	+

mesh

anonymous@undisclosed.example.com (Anonymous) — Wed, 29 Oct 2025 10:19:59 +0000

2025/02/24 15:27		current
Line 5:		Line 5:
	[[https://ui.adsabs.harvard.edu/abs/1979ApJ...234L.139L\|Interstellar methyl mercaptan]]\\		[[https://ui.adsabs.harvard.edu/abs/1979ApJ...234L.139L\|Interstellar methyl mercaptan]]\\
	//Astrophys. J.// 232, L139–L142 (1979).\\		//Astrophys. J.// 232, L139–L142 (1979).\\
-	6 features belonging to several more //J// = 3 –2 and 4 –3 were observed near 75.9 and near 101 GHz. The derived rotational temperature in that source was about 9 K.\\	+	6 features belonging to several more //J// = 3 – 2 and 4 – 3 were observed near 75.9 and near 101 GHz. The derived rotational temperature in that source was about 9 K.\\
	\\		\\

Line 40:		Line 40:
	[[https://doi.org/10.3847/2041-8213/adacea\|Laboratory Rotational Spectroscopy Leads to the First Interstellar Detection of Singly Deuterated Methyl Mercaptan (CH2DSH)]]\\		[[https://doi.org/10.3847/2041-8213/adacea\|Laboratory Rotational Spectroscopy Leads to the First Interstellar Detection of Singly Deuterated Methyl Mercaptan (CH2DSH)]]\\
	//Astrophys. J. Lett.// 980, Art. No. L13 (2025).\\		//Astrophys. J. Lett.// 980, Art. No. L13 (2025).\\
-		+	The isotopolog was identified in the Protostellar Interferometric Line Survey (PILS) toward the solar-like protostar IRAS 16293−2422 B. Eight lines were detected that were deemed to be unblended or only slightly blended. Several other transitions were covered, but most of them were severely blended. The derived CH<sub>2</sub>DSH to CH<sub>3</sub>SH ratio is about 0.055. An earlier search for CH<sub>3</sub>SD by [[https://doi.org/10.1051/0004-6361/201834472\|O. Zhakharenko et al.]], //Astron. Astrophys.// 621, Art. No. A114 (2019) was unsuccessful and, with respect to the present finding, not particularly constraining.\\
		+	\\

	----		----

mesih3

anonymous@undisclosed.example.com (Anonymous) — Fri, 26 Apr 2019 13:31:31 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Methyl Silane, CH3SiH3, in Space =====
	+
	+	J. Cernicharo, M. Agúndez, L. Velilla Prieto, M. Guélin, J. R. Pardo, C. Kahane, C. Marka, C. Kramer, S. Navarro, G. Quintana-Lacaci, J. P. Fonfría, N. Marcelino, B. Tercero, E. Moreno, S. Massalkhi, M. Santander-García, M. C. McCarthy, C. A. Gottlieb, and J. L. Alonso\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201731672\|Discovery of Methyl Silane and Confirmation of Silyl Cyanide in IRC +10216]]\\
	+	//Astron. Astrophys.// 606, Art. No. L5 (2017).\\
	+	8 sets of methyl silane, CH<sub>3</sub>SiH<sub>3</sub> transitions with //J'// between 4 and 16 (between 87 and 351 GHz) were detected with the IRAM 30 m telescope in emission toward the late-type C-rich star CW Leonis. The //K// levels are blended at low //J//, but partly resolved //K// level structure is seen at higher //J//. Some sets of transitions are slightly or strongly blended with emission lines of other molecules, but in all instances there are features not entirely blended.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2017
	+
	+
	+	----
	+

methoxyethanol

anonymous@undisclosed.example.com (Anonymous) — Mon, 29 Apr 2024 10:28:58 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Discovery of Methoxyethanol in the ISM =====
	+
	+	Z. T. P. Fried, S. J. El-Abd, B. M. Hays, G. Wenzel, A. N. Byrne, L. Margulès, R. A. Motiyenko, S. T. Shipman, M. P. Horne, J. K. Jørgensen, C. L. Brogan, T. R. Hunter, A. J. Remijan, A. Lipnicky, R. A. Loomis, and B. A. McGuire\\
	+	described the\\
	+	**[[https://doi.org/10.3847/2041-8213/ad37ff\|Rotational Spectrum and First Interstellar Detection of 2-methoxyethanol Using ALMA
	+	Observations of NGC6334I]]**\\
	+	//Astrophys. J. Lett.// 965, Art. No. L23 (2024).\\
	+	Methoxyethanol, CH<sub>3</sub>OCH<sub>2</sub>CH<sub>2</sub>OH, was detected toward the high mass star-forming region NGC 6334I in archival ALMA Band 4 data around 131 and around 145 GHz. An excitation temperature of ~140 K was derived with a methoxymethanol to methoxyethanol ratio of ~30. The molecules was not detected in archival Band 7 data of IRAS 16293−2422B with a lower limt of this ratio of > 56.\\
	+	\\
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 04, 2024
	+
	+	----

methoxymethanol

anonymous@undisclosed.example.com (Anonymous) — Tue, 10 Mar 2020 08:18:44 +0000

2019/07/09 17:04		current
Line 1:		Line 1:
	===== On the Detection of Methoxymethanol, CH3OCH2OH, in Space =====		===== On the Detection of Methoxymethanol, CH3OCH2OH, in Space =====

-	B. A. McGuire, C. N. Shingledecker, E. R. Willis, A. M. Burkhardt, S. El-Abd, R. A. Motiyenko, C. L. Brogan, T. R. Hunter, L. Margulès, J.-C. Guillemin, R. T. Garrod, E. Herbst, and A. J. Remijan,\\	+	B. A. McGuire, C. N. Shingledecker, E. R. Willis, A. M. Burkhardt, S. El-Abd, R. A. Motiyenko, C. L. Brogan, T. R. Hunter, L. Margulès, J.-C. Guillemin, R. T. Garrod, E. Herbst, and A. J. Remijan\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.3847/2041-8213/aaa0c3\|ALMA Detection of Interstellar Methoxymethanol (CH<sub>3</sub>OCH<sub>2</sub>OH)]],\\		[[https://doi.org/10.3847/2041-8213/aaa0c3\|ALMA Detection of Interstellar Methoxymethanol (CH<sub>3</sub>OCH<sub>2</sub>OH)]],\\
Line 11:		Line 11:
	[[https://doi.org/10.1051/0004-6361/201834417\|Chemical Segregation of Complex Organic O-bearing Species in Orion KL]]\\		[[https://doi.org/10.1051/0004-6361/201834417\|Chemical Segregation of Complex Organic O-bearing Species in Orion KL]]\\
	//Astron. Astrophys.// 620, Art. No. L6 (2018).\\		//Astron. Astrophys.// 620, Art. No. L6 (2018).\\
-	They analyzed the Cycle 0 ALMA science verification data and found ethyl methyl ether besides several other molecules.	+	They analyzed the Cycle 0 ALMA science verification data and found methoxymethanol besides several other molecules.

		+	S. Manigand, J. K. Jørgensen, H. Calcutt, H. S. P. Müller, N. F. W. Ligterink, A. Coutens, M. N. Drozdovskaya, E. F. van Dishoeck, and S. F. Wampfler\\
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/201834417\|The ALMA-PILS Survey: Inventory of Complex Organic Molecules towards IRAS 16293–2422 A]]\\
		+	//Astron. Astrophys.// 635, Art. No. A48 (2020).\\
		+	They found methoxymethanol toward the low-mass proto-star IRAS 16293–2422 B in this context.

-	----

-	Contributor(s): H. S. P. Müller; 12, 2017; 07, 2019	+	----

		+	Contributor(s): H. S. P. Müller; 12, 2017; 07, 2019; 03, 2020

	----		----

methylformiat

anonymous@undisclosed.example.com (Anonymous) — Mon, 07 Jul 2025 11:53:59 +0000

2025/07/07 13:43		current
Line 83:		Line 83:
	//Astrophys. J.// 755, Art. No. 153 (2012).\\		//Astrophys. J.// 755, Art. No. 153 (2012).\\
	The line survey covers the 1 to 50 GHz region. The three //K// = 0 transitions with //J"// = 0 to 2 were detected for both //A// and //E// internal rotation components. In addition, one //K// = 1 was detected for the //A// component. Two additional //K// = 1 transitions each were barely recognizable in the noise, the intensities being compatible with the model. The detection is probably not far from a definitive one.\\		The line survey covers the 1 to 50 GHz region. The three //K// = 0 transitions with //J"// = 0 to 2 were detected for both //A// and //E// internal rotation components. In addition, one //K// = 1 was detected for the //A// component. Two additional //K// = 1 transitions each were barely recognizable in the noise, the intensities being compatible with the model. The detection is probably not far from a definitive one.\\
		+
		+
		+	M. Sanz-Novo, G. Molpeceres, V. M. Rivilla, and I. Jimenez-Serra\\
		+	reinvestigated the\\
		+	[[https://doi.org/10.1051/0004-6361/202554686\|Conformational Isomerism of Methyl Formate: New Detections of the Higher-energy //trans// Conformer and Theoretical Insights]]\\
		+	//Astron. Astrophys.// 698, Art. No. A36 (2025).\\
		+	The conformer was identified in G+0.693−0.027, close to the Galactic center, and in L1157−B1. Both are cold and shocked sources, the latter one is considered to be a prototypical shock region. The //syn// to //anti// ("//cis//" to "//trans//") ratios are about 72 and 34, respectively, about factors of 7 and 3 higher than in the Sagittarius B2(N) envelope mentioned above.\\
	\\		\\

	----		----

-	Contributor(s): H. S. P. Müller; 02, 2007; 04, 2011; 07, 2012; 08, 2012; 11, 2016; 03, 2019	+	Contributor(s): H. S. P. Müller; 02, 2007; 04, 2011; 07, 2012; 08, 2012; 11, 2016; 03, 2019; 07, 2025

	----		----

methyloxiran

anonymous@undisclosed.example.com (Anonymous) — Fri, 19 Mar 2021 09:26:30 +0000

2019/02/25 22:38		current
Line 1:		Line 1:
-	===== Methyl Oxirane in the ISM =====	+	===== Methyloxirane in the ISM =====

-	The ring molecule methyl oxirane, CH<sub>3</sub>CHCH<sub>2</sub>O, also known as propylene oxide, was detected in the envelope of the prolific high-mass star-forming region Sagittarius B2(N) by\\	+	The ring molecule methyloxirane, CH<sub>3</sub>CHCH<sub>2</sub>O, also known as propylene oxide, was detected in the envelope of the prolific high-mass star-forming region Sagittarius B2(N) by\\
	B. A. McGuire, P. B. Carroll, R. A. Loomis, I. A. Finneran, P. R. Jewell, A. R. Remijan, and G. A. Blake,\\		B. A. McGuire, P. B. Carroll, R. A. Loomis, I. A. Finneran, P. R. Jewell, A. R. Remijan, and G. A. Blake,\\
-	[[http://dx.doi.org/10.1126/science.aae0328\|Discovery of the Interstellar Chiral Molecule Propylene Oxide (CH<sub>3</sub>CHCH<sub>2</sub>O)]]\\	+	[[https://doi.org/10.1126/science.aae0328\|Discovery of the Interstellar Chiral Molecule Propylene Oxide (CH<sub>3</sub>CHCH<sub>2</sub>O)]]\\
	//Science// 352, 1449 (2016).\\		//Science// 352, 1449 (2016).\\
	Three //<sup>r</sup>Q//<sub>0</sub> transition were detected in absorption; those with //J// = 2 and 3 near 12.84 and 14.05 GHz, respectively, were detected with the GBT 100 m dish, the Parkes 65 m dish was employed for the one with //J// = 1 near 12.07 GHz. Velocity issues were explained. The number of transitions may appear small, but the astronomical spectrum is relatively sparse in lines. More importantly, the inferred rotational temperature is about 5 K, appropriate for this less dense environment.\\		Three //<sup>r</sup>Q//<sub>0</sub> transition were detected in absorption; those with //J// = 2 and 3 near 12.84 and 14.05 GHz, respectively, were detected with the GBT 100 m dish, the Parkes 65 m dish was employed for the one with //J// = 1 near 12.07 GHz. Velocity issues were explained. The number of transitions may appear small, but the astronomical spectrum is relatively sparse in lines. More importantly, the inferred rotational temperature is about 5 K, appropriate for this less dense environment.\\

mex

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Sep 2020 13:33:25 +0000

2020/09/18 13:48		current
Line 3:		Line 3:
	E. C. Fayolle, K. I. Öberg, J. K. Jørgensen, K. Altwegg, H. Calcutt, H. S. P. Müller, M. Rubin, M. H. D. van der Wiel, P. Bjerkeli, T. L. Bourke, A. Coutens, E. F. van Dishoeck, M. N. Drozdovskaya, R. T. Garrod, N. F. W. Ligterink, M. V. Persson, S. F. Wampfler, and the ROSINA team\\		E. C. Fayolle, K. I. Öberg, J. K. Jørgensen, K. Altwegg, H. Calcutt, H. S. P. Müller, M. Rubin, M. H. D. van der Wiel, P. Bjerkeli, T. L. Bourke, A. Coutens, E. F. van Dishoeck, M. N. Drozdovskaya, R. T. Garrod, N. F. W. Ligterink, M. V. Persson, S. F. Wampfler, and the ROSINA team\\
	reported on the\\		reported on the\\
-	[[https://doi.org/%2010.1038/s41550-017-0237-7\|Protostellar and Cometary Detections of Organohalogens]]\\	+	[[https://doi.org/10.1038/s41550-017-0237-7\|Protostellar and Cometary Detections of Organohalogens]]\\
	//Nat. Astron.// 1 (2017), 703–708.\\		//Nat. Astron.// 1 (2017), 703–708.\\
	The //J// = 13 – 12 transitions with //K// = 0 to 4 of methyl chloride, CH<sub>3</sub>Cl, were detected with ALMA near 345.4 and 340.1 GHz for the <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs, respectively, in emission toward the Solar-type protostar IRAS 16293–2422B. CH<sub>3</sub><sup>35</sup>Cl was also seen toward the companion IRAS 16293–2422A. The <sup>35</sup>Cl/<sup>37</sup>Cl ratio is about 2.1, the same as observed for HCl in that source, but slightly lower than 3.13 on Earth.\\		The //J// = 13 – 12 transitions with //K// = 0 to 4 of methyl chloride, CH<sub>3</sub>Cl, were detected with ALMA near 345.4 and 340.1 GHz for the <sup>35</sup>Cl and <sup>37</sup>Cl isotopologs, respectively, in emission toward the Solar-type protostar IRAS 16293–2422B. CH<sub>3</sub><sup>35</sup>Cl was also seen toward the companion IRAS 16293–2422A. The <sup>35</sup>Cl/<sup>37</sup>Cl ratio is about 2.1, the same as observed for HCl in that source, but slightly lower than 3.13 on Earth.\\

mgc2_4h

anonymous@undisclosed.example.com (Anonymous) — Fri, 03 Sep 2021 15:29:40 +0000

2021/09/03 17:12		current
Line 23:		Line 23:
	[[https://doi.org/10.1051/0004-6361/202141671\|Magnesium Radicals MgC<sub>5</sub>N and MgC<sub>6</sub>H in IRC +10216]]\\		[[https://doi.org/10.1051/0004-6361/202141671\|Magnesium Radicals MgC<sub>5</sub>N and MgC<sub>6</sub>H in IRC +10216]]\\
	//Astron. Astrophys.// 652, Art. No. L13 (2021).\\		//Astron. Astrophys.// 652, Art. No. L13 (2021).\\
-	The 40 m Centro Astronómico de Yebes dish was employed to observe 16 rotational transitions of magnesium monotriacetylide, MgC<sub>6</sub>H, with //N"// = 26 to 41 between 31.0 and 50.3 GHz toward the famous near-by carbon-rich AGB star CW Leonis. Some of the transitions displayed resolved fine structure (FS) splitting. 10 transitions appear to be unblended or only slightly blended, one FS component each was sufficiently clear for two more transitions. The identification of a new species is unambiguous. The identification of the carrier may be viewed with slight caution in the absence of laboratory data. However, the FS spltting is a very strong indicator. It is very interesting to note that the triacetylide and the diacetylide have about the same column densities, and both are about a factor of 10 more abundant than MgC<sub>2</sub>H. The authors justified this by their likely formation which involves radiative association reactions of Mg<sup>+</sup> with C<sub>2n</sub>H<sub>2</sub>.\\	+	The 40 m Centro Astronómico de Yebes dish was employed to observe 16 rotational transitions of magnesium monotriacetylide, MgC<sub>6</sub>H, with //N"// = 26 to 41 between 31.0 and 50.3 GHz toward the famous near-by carbon-rich AGB star CW Leonis. Some of the transitions displayed resolved fine structure (FS) splitting. 10 transitions appear to be unblended or only slightly blended, one FS component each was sufficiently clear for two more transitions. The identification of a new species is unambiguous. The identification of the carrier may be viewed with slight caution in the absence of laboratory data. However, the FS spltting is a very strong indicator that the identification is unambiguous as well. It is very interesting to note that the triacetylide and the diacetylide have about the same column densities, and both are about a factor of 10 more abundant than MgC<sub>2</sub>H. The authors justified this by their likely formation which involves radiative association reactions of Mg<sup>+</sup> with C<sub>2n</sub>H<sub>2</sub>. These ratios are quite similar to those observed for the isoelectronic MgC<sub>2n+1</sub>N molecules.\\

	----		----

mgc2

anonymous@undisclosed.example.com (Anonymous) — Fri, 16 Dec 2022 12:39:06 +0000

2022/12/16 13:37		current
Line 6:		Line 6:
	[[https://doi.org/10.3847/2041-8213/aca144\|Laboratory and Astronomical Discovery of Magnesium Dicarbide, MgC<sub>2</sub>]]\\		[[https://doi.org/10.3847/2041-8213/aca144\|Laboratory and Astronomical Discovery of Magnesium Dicarbide, MgC<sub>2</sub>]]\\
	//Astrophys. J. Lett// 940, Art. No. L42 (2022).\\		//Astrophys. J. Lett// 940, Art. No. L42 (2022).\\
-	Ten //a//-type lines with 1 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 4 between 41 and 150 GHz were identified for the main <sup>24</sup>Mg isotopolog employing the Yebes 40 m and IRAM 30 m dishes in the couses of molecular line surveys of CW Leonis. These lines have good to reasonable signal-to-noise ratios, and several lines are unblended. One and three lines were identified for the <sup>25</sup>Mg and <sup>26</sup>Mg minor isotopologs, respectively. The isotopic ratios is compatible with solar values within uncertainties. The derived MgC<sub>2</sub> : MgC<sub>2</sub>H : MgC<sub>4</sub>H : MgC<sub>6</sub>H abundance raios are about 1 : 2 : 22 : 20.\\	+	Ten //a//-type lines with 1 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 4 between 41 and 150 GHz were identified for the main <sup>24</sup>Mg isotopolog employing the Yebes 40 m and IRAM 30 m dishes in the couses of molecular line surveys of CW Leonis. These lines have good to reasonable signal-to-noise ratios, and several lines are unblended. One and three lines were identified for the <sup>25</sup>Mg and <sup>26</sup>Mg minor isotopologs, respectively. The isotopic ratios are compatible with solar values within uncertainties. The derived MgC<sub>2</sub> : MgC<sub>2</sub>H : MgC<sub>4</sub>H : MgC<sub>6</sub>H abundance raios are about 1 : 2 : 22 : 20.\\
	\\		\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 12, 2022
		+
		+	----
		+

mgc2nh-plus

anonymous@undisclosed.example.com (Anonymous) — Thu, 07 Sep 2023 10:17:56 +0000

2023/05/09 14:15		current
Line 11:		Line 11:
	Seven successive transitions with 11 ≤ //J"// ≤ 17 were identified for MgC<sub>3</sub>N<sup>+</sup> of which five were partially blended.		Seven successive transitions with 11 ≤ //J"// ≤ 17 were identified for MgC<sub>3</sub>N<sup>+</sup> of which five were partially blended.
	16 transitions with 27 ≤ //J"// ≤ 42 were accessed in the case of MgC<sub>5</sub>N<sup>+</sup>. Nine were partially blended, one heavily, and two lines were too week to be detected securely.		16 transitions with 27 ≤ //J"// ≤ 42 were accessed in the case of MgC<sub>5</sub>N<sup>+</sup>. Nine were partially blended, one heavily, and two lines were too week to be detected securely.
-	The rotational temperatures are around 20 K; the value of ~10 K for MgC<sub>3</sub>N<sup>+</sup> should probably viewed with great caution.\\	+	The rotational temperatures are around 20 K; the value of ~10 K for MgC<sub>3</sub>N<sup>+</sup> should probably be viewed with great caution. The abundance ratios are about 48 : 12 : 25 : 11 for MgC<sub>4</sub>H<sup>+</sup>, MgC<sub>3</sub>N<sup>+</sup>. MgC<sub>6</sub>H<sup>+</sup>, and MgC<sub>5</sub>N<sup>+</sup>, respectively. The cations are about a factor of 200 less abundant than their neutral counterparts in the case of MgC<sub>4</sub>H<sup>+</sup> and MgC<sub>6</sub>H<sup>+</sup>, whereas is is about a factor of 100 for MgC<sub>3</sub>N<sup>+</sup> and about a factor of 50 for MgC<sub>5</sub>N<sup>+</sup>. Again, the ratios for MgC<sub>3</sub>N<sup>+</sup> should be viewed with caution.\\
		+	\\

	----		----

mgc3n

anonymous@undisclosed.example.com (Anonymous) — Fri, 03 Sep 2021 15:30:37 +0000

2019/10/23 17:22		current
Line 1:		Line 1:
-	===== Detection of Magnesium Monocyanoacetylide, MgC<sub>3</sub>N, toward CW Leonis =====	+	===== Detection of Magnesium Monocyanoacetylides toward CW Leonis =====

	J. Cernicharo, C. Cabezas, J. R. Pardo, M. Agúndez, C. Bermúdez, L. Velilla-Prieto, F. Tercero, J. A. López-Pérez, J. D. Gallego, J. P. Fonfría, G. Quintana-Lacaci, M. Guélin, and Y. Endo\\		J. Cernicharo, C. Cabezas, J. R. Pardo, M. Agúndez, C. Bermúdez, L. Velilla-Prieto, F. Tercero, J. A. López-Pérez, J. D. Gallego, J. P. Fonfría, G. Quintana-Lacaci, M. Guélin, and Y. Endo\\
Line 6:		Line 6:
	MgC<sub>3</sub>N and MgC<sub>4</sub>H]]**\\		MgC<sub>3</sub>N and MgC<sub>4</sub>H]]**\\
	//Astron. Astrophys.// 630, Art. No. L2 (2019).\\		//Astron. Astrophys.// 630, Art. No. L2 (2019).\\
-	The 40 m Centro Astronómico de Yebes dish and the IRAM 30 m dish were employed to observed 22 rotational transitions of magnesium monocyanoacetylide, MgC<sub>3</sub>N, between //N'// = 12 and 40 and between 33 and 111 GHz toward the famous near-by carbon-rich AGB star CW Leonis. Many transitions show decent to good signal-to-noise ratios and are not or only slightly blended. Fine structure splitting is well-resolved at lower frequencies. The astronomical data were employed to derive spectroscopic parameters in the absence of laboratory data.	+	The 40 m Centro Astronómico de Yebes dish and the IRAM 30 m dish were employed to observed 22 rotational transitions of magnesium monocyanoacetylide, MgC<sub>3</sub>N, between //N'// = 12 and 40 and between 33 and 111 GHz toward the famous near-by carbon-rich AGB star CW Leonis. Many transitions show decent to good signal-to-noise ratios and are not or only slightly blended. Fine structure splitting is well-resolved at lower frequencies. The astronomical data were employed to derive spectroscopic parameters in the absence of laboratory data.\\
		+
		+	\\
		+	J. R. Pardo, C. Cabezas, J. P. Fonfría, M. Agúndez, B. Tercero, P. de Vicente, M. Guélin and J. Cernicharo
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/202141671\|Magnesium Radicals MgC<sub>5</sub>N and MgC<sub>6</sub>H in IRC +10216]]\\
		+	//Astron. Astrophys.// 652, Art. No. L13 (2021).\\
		+	The 40 m Centro Astronómico de Yebes dish was employed to observe 15 rotational transitions of magnesium cyanodiacetylide, MgC<sub>5</sub>N, with //N"// = 27 to 41 between 31.0 and 50.3 GHz toward the famous near-by carbon-rich AGB star CW Leonis. Some of the transitions displayed resolved fine structure (FS) splitting. 14 transitions appear to be unblended or only slightly blended. The identification of a new species is unambiguous. The identification of the carrier may be viewed with slight caution in the absence of laboratory data. However, the FS spltting is a very strong indicator that the identification is unambiguous as well. It is very interesting to note that MgC<sub>5</sub>N has a column density only a factor of two lower than that of MgC<sub>3</sub>N, but about a factor of six higher than that of MgCN. The authors justified this by their likely formation which involves radiative association reactions of Mg<sup>+</sup> with HC<sub>2n+1</sub>N. These ratios are similar to those of the isoelectronic MgC<sub>2n</sub>H molecules. MgNC is about a factor of three more abundant than MgC<sub>5</sub>N.\\


	----		----

-	Contributor(s): H. S. P. Müller; 10, 2019	+	Contributor(s): H. S. P. Müller; 10, 2019; 09, 2021

	----		----

mnc_mcn

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 20:18:34 +0000

n-mefo

anonymous@undisclosed.example.com (Anonymous) — Wed, 26 Nov 2025 14:00:37 +0000

2025/11/26 14:53		current
Line 19:		Line 19:
	[[https://doi.org/10.1051/0004-6361/202556709\|High-energy Interstellar Isomers: cis-N-methylformamide in the G+0.693−0.027 molecular cloud]]\\		[[https://doi.org/10.1051/0004-6361/202556709\|High-energy Interstellar Isomers: cis-N-methylformamide in the G+0.693−0.027 molecular cloud]]\\
	//Astron. Astrophys.// 628, Art. No. A10 (2019).\\		//Astron. Astrophys.// 628, Art. No. A10 (2019).\\
-		+	Several unblended to slightly blended lines of the barely higher lying conformer were detecetd toward the cold and presumably shocked molecular cloud G+0.693−0.027 close to Sagittarius B2(N).\\
		+	\\

	----		----

-	Contributor(s): H. S. P. Müller; 07, 2017; 07, 2019	+	Contributor(s): H. S. P. Müller; 07, 2017; 07, 2019; 11, 2025

	----		----

n2

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:21:23 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of the Nitrogen Molecule, N2, in the ISM =====
	+
	+	D. C. Knauth, B.-G. Andersson, S. R. McCandliss, and H. W. Moos\\
	+	reported on\\
	+	[[https://doi.org/10.1038/nature02614\|The Interstellar N<sub>2</sub> Abundance Towards HD 124314 from Far-Ultraviolet Observations]]\\
	+	//Nature// 429, 636–638 (2004).\\
	+	The Far Ultraviolet Spectroscopic Explorer (Fuse) was used to identify N<sub>2</sub> in the diffuse medium toward the slightly reddened star HD 124314, which is also known as IRAS 14111–6127, via its c'<sub>4</sub> – X electronic transition at 95.86 nm and the c<sub>3</sub> – X transition at 96.03 nm. The material is considered to be diffuse rather than translucent because of the slight reddening of the star. However, the derived fractional abundance of N<sub>2</sub> with respect to H<sub>2</sub> is about 3.3 × 10<sup>–7</sup>, two orders of magnitude higher than predictions from diffuse ISM models from that time. On the other hand, the column density is slightly less than that of CO on the same line of sight, and the deduced temperature is identical to that of the cold H<sub>2</sub> component (about 38 K). Moreover, similar observations of NH also yielded relative abundances much higher than predicted by diffuse ISM models.\\
	+	See also the news and views contribution by\\
	+	T. P. Snow,\\
	+	[[https://doi.org/10.1038/429615a\|Molecular Nitrogen in Space]]\\
	+	//Nature// 429, 615–616 (2004).
	+
	+	The same authors reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/2006ASPC..348..421K\|Discovery of Interstellar N<sub>2</sub>]]\\
	+	Proceedings of the "Astrophysics in the Far Ultraviolet: Five Years of Discovery with FUSE" Conference, 2–6 Aug, 2004, Victoria, BC, Canada; ASP Conference Series, Vol. 348, 421–423.\\
	+	Besides their observations mentioned above, they report on N<sub>2</sub> detection toward 20 Aql, aka HD 179406, however, with a fractional abundance wrt H<sub>2</sub> almost one order of magnitude less than toward HD 124314.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 11, 2016
	+
	+	----
	+

nacccn

anonymous@undisclosed.example.com (Anonymous) — Mon, 08 May 2023 14:29:58 +0000

2023/05/08 16:21		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202346462\|Discovery of Two Metallic Cyanoacetylides in IRC +10216: HMgCCCN and NaCCCN]]\\		[[https://doi.org/10.1051/0004-6361/202346462\|Discovery of Two Metallic Cyanoacetylides in IRC +10216: HMgCCCN and NaCCCN]]\\
	//Astron. Astrophys.// 672, Art. No. L12 (2023).\\		//Astron. Astrophys.// 672, Art. No. L12 (2023).\\
-	The molecule was identified in the course of a molecular line survey between 31.0 and 50.3 GHz through four unblendand two slightly blended transitions. One further line was heavily blended and the one at highest frequency was slightly too weak to be observed.	+	The molecule was identified in the course of a molecular line survey with the 40 m Yebes radio telescope between 31.0 and 50.3 GHz through seven transitions of which one was slightly and one heavily blended. The rotational temperature is about 13.5 K. It is less abundant than sodium (iso) cyanide by a factor of about 250 to 750.\\
-	The identification relied on quantum chemical calculations in the absense of laboratory spectroscopic data. The rotational temperature is roughly 17 K. The abundance ratios of HMgC<sub>3</sub>N : MgCN : MgC<sub>3</sub>N : MgC<sub>5</sub>N : MgNC : HMgNC are about 30 : 7.4 : 93 : 47 : 130 : 6.\\	+

	----		----

nc_ns

anonymous@undisclosed.example.com (Anonymous) — Tue, 02 Sep 2025 14:29:29 +0000

2024/11/26 13:34		current
Line 1:		Line 1:
	===== On NC<sub>n</sub>S (n ≥ 2) Radicals in the ISM =====		===== On NC<sub>n</sub>S (n ≥ 2) Radicals in the ISM =====

-	J. Cernicharo, C. Cabezas, M. Agúndez, R. Fuentetaja, B. Tercero, N. Marcelino, and P. de Vicente\\	+	J. Cernicharo, C. Cabezas, M. Agúndez, R. Fuentetaja, B. Tercero, N. Marcelino, and P. de Vicente\\
	announced\\		announced\\
	[[https://doi.org/10.1051/0004-6361/202451256\|More sulphur in TMC-1: Discovery of the NC<sub>3</sub>S and HC<sub>3</sub>S radicals with the QUIJOTE line survey]]\\		[[https://doi.org/10.1051/0004-6361/202451256\|More sulphur in TMC-1: Discovery of the NC<sub>3</sub>S and HC<sub>3</sub>S radicals with the QUIJOTE line survey]]\\
	//Astron. Astrophys.// 688, Art. No. L13 (2024).\\		//Astron. Astrophys.// 688, Art. No. L13 (2024).\\
-	Cyanoethenthionyl in it <sup>2</sup>π<sub>3/2</sub> lower spin ladder was detected through five consecutive transitions with 23/2 ≤ //J'// ≤ 33/2 between 33.0 and 47.5 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The first two lines display somewhat and barely resolved <sup>14</sup>N hyperfine structure splitting, respectively. The next two lines are somewhat broadened, and the last line is blended. Members with //n// = 2 and //n// ≥ 4 were not detected. The abundance ratios of NCS/NC<sub>3</sub>S is about 5.6.\\	+	Cyanoethynylsulfanyl in it <sup>2</sup>π<sub>3/2</sub> lower spin ladder was detected through five consecutive transitions with 23/2 ≤ //J'// ≤ 33/2 between 33.0 and 47.5 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The first two lines display somewhat and barely resolved <sup>14</sup>N hyperfine structure splitting, respectively. The next two lines are somewhat broadened, and the last line is blended. Members with //n// = 2 and //n// ≥ 4 were not detected. The abundance ratios of NCS/NC<sub>3</sub>S is about 5.6.\\
	\\		\\

nc4nh-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 28 Dec 2022 10:08:05 +0000

2022/12/27 14:07		current
Line 4:		Line 4:
	reported on\\		reported on\\
	[[https://doi.org/10.1051/0004-6361/202245492\|Discovery of Interstellar NC<sub>4</sub>NH<sup>+</sup>: Dicyanopolyynes are indeed Abundant in Space]],\\		[[https://doi.org/10.1051/0004-6361/202245492\|Discovery of Interstellar NC<sub>4</sub>NH<sup>+</sup>: Dicyanopolyynes are indeed Abundant in Space]],\\
-	//Astron. Astrophys.// 669, Art. No. L1 (2022).\\	+	//Astron. Astrophys.// 669, Art. No. L1 (2023).\\
-	Six consecutive transitions with 12 ≤ //J"// ≤ 17 between 33.6 and 46.6 GHz were identified in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz with good signal-to-noise ratio, except for the highest //J//, where it was still reasonable. The molecule was identified based on the proximity to scaled spectroscopic parameters from a quantum-chemical calculation. The parameters of HC<sub>5</sub>NH<sup>+</sup>, for which also no laboratory data are available at present, are very similar. However, the scaled parameters agree much better with those from astronomical observations with the current identifications. Additional support come from the fact that the molecule with the larger dipole moment, NC<sub>4</sub>NH<sup>+</sup>, has a rotation temperature of ∼6 K whereas the one of HC<sub>5</sub>NH<sup>+</sup> is ~8 K. NC<sub>4</sub>NH<sup>+</sup> is about eight times less abundant in TMC-1 than NC<sub>2</sub>NH<sup>+</sup>.\\	+	Six consecutive transitions with 12 ≤ //J"// ≤ 17 between 33.6 and 46.6 GHz were identified in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz with good signal-to-noise ratio, except for the highest //J//, where it was still reasonable. The molecule was identified based on the proximity of the astronomically derived spectroscopic parameters to scaled ones from a quantum-chemical calculation. The parameters of HC<sub>5</sub>NH<sup>+</sup>, for which also no laboratory data are available at present, are very similar. However, the scaled parameters agree much better with those from astronomical observations with the current identifications. Additional support come from the fact that the molecule with the larger dipole moment, NC<sub>4</sub>NH<sup>+</sup>, has a rotation temperature of ∼6 K whereas the one of HC<sub>5</sub>NH<sup>+</sup> is ~8 K. NC<sub>4</sub>NH<sup>+</sup> is about eight times less abundant in TMC-1 than NC<sub>2</sub>NH<sup>+</sup>.\\
	\\		\\

nccnh-plus

anonymous@undisclosed.example.com (Anonymous) — Tue, 27 Dec 2022 12:47:14 +0000

nchccs

anonymous@undisclosed.example.com (Anonymous) — Fri, 31 May 2024 12:11:21 +0000

2024/05/27 12:41		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202450323\|Laboratory and astronomical discovery of cyanothioketene, NCCHCS, in the cold starless core TMC-1]]\\		[[https://doi.org/10.1051/0004-6361/202450323\|Laboratory and astronomical discovery of cyanothioketene, NCCHCS, in the cold starless core TMC-1]]\\
	//Astron. Astrophys.// 686, (2024), Art. No. L3.\\		//Astron. Astrophys.// 686, (2024), Art. No. L3.\\
-	The molecule was identified in the course of a line survey carried out with the Yebes 40 m dishe. 23 //a//-type transitions with 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 2 were detected between 31 and 50 GHz with good to reasnable signal-to-noise ratios. The thioketene to cyanothioketene ratio is as low as ~6.5, while the ratio of the more abundant thioformaldehyde to cyanothioformaldehyde is ~28. Cyanoketene was not detected, and the ketene to cyanoketene is >	+	The molecule, which is also known as cyanoethenthione, was identified in the course of a line survey carried out with the Yebes 40 m dishe. 23 //a//-type transitions with 8 ≤ //J// ≤ 14 and //K<sub>a</sub>// ≤ 2 were detected between 31 and 50 GHz with good to reasnable signal-to-noise ratios. The thioketene to cyanothioketene ratio is as low as ~6.5, while the ratio of the more abundant thioformaldehyde to cyanothioformaldehyde is ~28. Cyanoketene was not detected, and the ketene to cyanoketene is > ~430. Judging by the formaldehyde to cyanoformaldehyde ratio of ~1400, the observation of cyanoketene may require only a modest increase in sensitivity.\\
-	the formaldehyde to cyanoformaldehyde\\	+
	\\		\\

Line 14:		Line 13:

	----		----
-

nco

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Feb 2019 21:38:46 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Cyanate Radical, NCO, in the ISM =====
	+
	+	N. Marcelino, M. Agúndez, J. Cernicharo, E. Roueff, and M. Tafalla\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201833074\|Discovery of the Elusive Radical NCO and Confirmation of H<sub>2</sub>NCO<sup>+</sup> in Space]]\\
	+	//Astron. Astrophys.// 612, Art. No. L10 (2018).\\
	+	The cyanate (or isocyanate) radical was detected in the course of a 3 mm line survey of the dense core L483 toward the young stellar object IRAS 18148–0440 carried out with the IRAM 30 m telescope. Two Λ-components were detected in emission for each of the three strong hyperfine components of two transitions, //J// = 3.5 – 2.5 near 81.411 GHz and //J// = 4.5 – 3.5 near 104.67 GHz. The derived abundance is only about a factor of five lower than that of HNCO.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2018
	+
	+
	+	----
	+

ncs

anonymous@undisclosed.example.com (Anonymous) — Tue, 13 Apr 2021 11:15:47 +0000

2021/04/13 13:06		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202140642\|TMC-1, the starless core sulfur factory: Discovery of NCS, HCCS, H<sub>2</sub>CCS, H<sub>2</sub>CCCS, and C<sub>4</sub>S and detection of C<sub>5</sub>S]]\\		[[https://doi.org/10.1051/0004-6361/202140642\|TMC-1, the starless core sulfur factory: Discovery of NCS, HCCS, H<sub>2</sub>CCS, H<sub>2</sub>CCCS, and C<sub>4</sub>S and detection of C<sub>5</sub>S]]\\
	//Astron. Astrophys.// 648, Art. No. L3 (2021).\\		//Astron. Astrophys.// 648, Art. No. L3 (2021).\\
-	Three <sup>14</sup>N hyperfine components of the <sup>2</sub>Π<sub>3/2</sub> //J// = 5/2 − 3/2 transition of NCS were detected in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The column density is slightly higher than those of HSCN and HNCS.\\	+	Three <sup>14</sup>N hyperfine components of the <sup>2</sup>Π<sub>3/2</sub> //J// = 5/2 − 3/2 transition of NCS were detected near 42.7 GHz in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope. The column density is slightly higher than those of HSCN and HNCS.\\

nh

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:52:12 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Imidogen, NH, in the Interstellar Medium =====
	+
	+	One and two transitions of the //A// <sup>3</sup>Π – //X// <sup>3</sup>Σ electronic spectrum of imidogen near 335 nm were detected in diffuse clouds toward ζ Per and HD 27778, respectively:\\
	+	D. M. Meyer and K. C. Roth,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1991ApJ...376L..49M\|Discovery of Interstellar NH]]\\
	+	//Astrophys. J.// 376, L49–L52 (1991).\\
	+	The transitions involve an //R//(0) component in both cases as well as a //Q//(0) component of the //v// = 0 – 0 vibrational band system near 335.8 and 335.4 nm, respectively.
	+
	+	The detection of one fine struture component of the //N// = 2 – 1 pure rotational transition toward Sgr B2 was reported by\\
	+	J. Cernicharo, J. R. Goicoechea, and E. Caux,\\
	+	[[https://doi.org/10.1086/312668\|Far-Infrared Detection of C<sub>3</sub> in Sagittarius B2 and IRC +10216]]\\
	+	//Astrophys. J.// 534, L199–L202 (2000);\\
	+	a second fine structure component of that transition was reported in\\
	+	J. R. Goicoechea, N. J. Rodríguez-Fernández and J. Cernicharo,\\
	+	**[[https://doi.org/10.1086/379704\|The Far-Infrared Spectrum of the Sagittarius B2 Region:\\
	+	Extended Molecular Absorption, Photodissociation, and Photoionization]]**\\
	+	//Astrophys. J.// 600, 214–233 (2004).
	+
	+	A plethora of reports on observations of one or more fine structure components of the //N// = 1 – 0 transition in absorption carried out with //Herschel///HIFI were reported in the HIFI special issue of A&A. In, at least, most instances, the observatioon of absorption lines indicates the presence of NH in diffuse gas. The objects investigated include\\
	+	a photon-dominated region: A. Fuente, O. Berné, J. Cernicharo, et al.:\\
	+	[[https://doi.org/10.1051/0004-6361/201015093\|Herschel Observations in the Ultracompact HII Region Mon R2 – Water in Dense Photon-Dominated Regions (PDRs)]]\\
	+	//Astron. Astrophys.// 521, Art. No. L23 (2010);\\
	+	a young stellar object: A. O. Benz, S. Bruderer, E. F. van Dishoeck, et al.:\\
	+	[[https://doi.org/10.1051/0004-6361/201015111\|Hydrides in Young Stellar Objects: Radiation Tracers in a Protostar-Disk-Outflow System]]\\
	+	//Astron. Astrophys.// 521, Art. No. L35 (2010);\\
	+	the sight line toward a high-mass star-forminbg region: C. M. Persson, J. H. Black, J. Cernicharo, et al.:\\
	+	[[https://doi.org/10.1051/0004-6361/201015105\|Nitrogen Hydrides in Interstellar Gas – //Herschel///HIFI Observations towards G10.6-0.4 (W31C)]]\\
	+	//Astron. Astrophys.// 521, Art. No. L45 (2010);\\
	+	and another young stellar object: P. Hily-Blant, S. Maret, A. Bacmann, et al.:\\
	+	[[https://doi.org/10.1051/0004-6361/201015253\|Nitrogen Cydrides in the Cold Envelope of IRAS 16293-2422]]\\
	+	//Astron. Astrophys.// 521, Art. No. L52 (2010).
	+
	+	In this context, also ND was observed in two fine structure components of the //N// = 1 – 0 transition by:\\
	+	A. Bacmann, E. Caux, P. Hily-Blant, et al.\\
	+	[[https://doi.org/10.1051/0004-6361/201015102\|First Detection of ND in the Solar-Mass Protostar IRAS 16293-2422]]\\
	+	//Astron. Astrophys.// 521, Art. No. L42 (2010).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 03, 2007; 04, 2011
	+
	+
	+	----
	+

nh2

anonymous@undisclosed.example.com (Anonymous) — Fri, 10 Feb 2023 15:31:14 +0000

2023/02/10 16:10		current
Line 18:		Line 18:
	[[https://doi.org/10.1051/0004-6361/202038490\|First detection of NHD and ND2 in the interstellar medium — Amidogen deuteration in IRAS 16293–2422]]\\		[[https://doi.org/10.1051/0004-6361/202038490\|First detection of NHD and ND2 in the interstellar medium — Amidogen deuteration in IRAS 16293–2422]]\\
	//Astron. Astrophys.// 641, Art. No. A153 (2020).\\		//Astron. Astrophys.// 641, Art. No. A153 (2020).\\
-	Both isotopologs were detected in archival HIFI///Herschel// data taken toward the Class 0 protostar IRAS 16293−2422	+	Both isotopologs were detected in archival HIFI///Herschel// data taken toward the Class 0 protostar IRAS 16293−2422. Very high degrees of deuteration were inferred.\\
		+	\\

		+	A similar account was given shortly thereafter by\\
		+	A. Bacmann, A. Faure, P. Hily-Blant, K. Kobayashi, H. Ozeki, S. Yamamoto, L. Pagani, and F. Lique,\\
		+	[[https://doi.org/10.1093/mnras/staa2903\|Deuterium fractionation of nitrogen hydrides: detections of NHD and ND2]]\\
		+	//Mon. Not. R. Astron. Soc.// 499, 1795 (2020).\\
		+	NHD observations are based on archival APEX data, ND<sub>2</sub> observations on archival HIFI///Herschel// data as above. The numbers are very similar to the ones above. One can deduce deuteration degrees per A atom of ~0.25 and ~0.35 for NHD and ND<sub>2</sub>, respectively, from their total column densities.\\
		+	\\

	----		----

nh2oh

anonymous@undisclosed.example.com (Anonymous) — Wed, 02 Sep 2020 09:58:12 +0000

2020/08/24 11:17		current
Line 7:		Line 7:
	The detection of five rotational transitions of the hydroxylamine were reported. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), with the IRAM 30 m dish at 3 and 2 mm. The //a//-type transitions cover //J// = 2−1, 3−2, and 4−3 near 100.7, 151.1, and 201.5 GHz. The formation of NH<sub>2</sub>OH appears to be favored by a high column density of NO. The NO to NH<sub>2</sub>OH ratio is about 1000. The inferred rotational temperature of 15 K is a value typical for dark clouds.\\		The detection of five rotational transitions of the hydroxylamine were reported. The observations were part of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), with the IRAM 30 m dish at 3 and 2 mm. The //a//-type transitions cover //J// = 2−1, 3−2, and 4−3 near 100.7, 151.1, and 201.5 GHz. The formation of NH<sub>2</sub>OH appears to be favored by a high column density of NO. The NO to NH<sub>2</sub>OH ratio is about 1000. The inferred rotational temperature of 15 K is a value typical for dark clouds.\\

-	A plethora of unsuccessful searches for hydroxylamine have been reported in the literature, but these searches were all carried out toward star-forming regions. The unsuccesful searches in hot cores or hot corinos or in their colder and less dense envelopes, however, rule out a prominent role of hydroxylamine as a prebiotic precursor of the primordial RNA world in space.\\	+	A plethora of unsuccessful searches for hydroxylamine have been reported in the literature, but these searches were all carried out toward star-forming regions. The non-observations thus far in hot cores or hot corinos or in their colder and less dense envelopes, however, rule out a prominent role of hydroxylamine as a prebiotic precursor of the primordial RNA world in space at present.\\

no-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 25 May 2022 14:07:50 +0000

2019/02/25 22:38		current
Line 1:		Line 1:
-	===== On Nitrosylium in Space =====	+	===== On Nitrosylium, NO+, in Space =====

	J. Cernicharo, S. Bailleux, E. Alekseev, A. Fuente, E. Roueff, M. Gerin, B. Tercero, S. P. Treviño-Morales, N. Marcelino, R. Bachiller, and B. Lefloch,\\		J. Cernicharo, S. Bailleux, E. Alekseev, A. Fuente, E. Roueff, M. Gerin, B. Tercero, S. P. Treviño-Morales, N. Marcelino, R. Bachiller, and B. Lefloch,\\
	reported on the\\		reported on the\\
-	[[http://dx.doi.org/10.1088/0004-637X/795/1/40\|Tentative Detection of the Nitrosylium Ion in Space]]\\	+	[[https://doi.org/10.1088/0004-637X/795/1/40\|Tentative Detection of the Nitrosylium Ion in Space]]\\
	//Astrophys. J.// 795, Art. No. 40 (2014).\\		//Astrophys. J.// 795, Art. No. 40 (2014).\\
-	The //J// = 2 – 1 transition of NO<sup>+</sup> near 238.4 GHz was idenitified in a line survey of the cold core Barnard 1-b carried out with the IRAM 30 m radio telescope. The two strongest overlapping HFS components were clearly seen in emission. There is also emission at the position of two weaker overlapping HFS components, though noise makes this feature appear stronger than expected. An expected third feature is in the noise. The reported abundance ratios, about similar among NO<sup>+</sup> and HNO, and NO being about 500 times more abundant than NO<sup>+</sup>, are quite reasonable, though agreement with model calculations were not entirely satisfactory for HNO.	+	The //J// = 2 – 1 transition of NO<sup>+</sup> near 238.4 GHz was idenitified in a line survey of the cold core Barnard 1-b carried out with the IRAM 30 m radio telescope. The two strongest overlapping HFS components were clearly seen in emission. There is also emission at the position of two weaker overlapping HFS components, though noise makes this feature appear stronger than expected. An expected third feature is in the noise. The reported abundance ratios, about similar among NO<sup>+</sup> and HNO, and NO being about 500 times more abundant than NO<sup>+</sup>, are quite reasonable, though agreement with model calculations were not entirely satisfactory for HNO.\\
		+	\\

		+	V. M. Rivilla, J. G. De La Concepción, I. Jiménez-Serra, J. Martín-Pintado, L. Colzi, B. Tercero, A. Megías, Á. López-Gallifa, A. Martínez-Henares, S. Massalkhi, S. Martín, S. Zeng, P. De Vicente, F. Rico-Villas, M. A. Requena-Torres, and G. Cosentino\\
		+	announced\\
		+	[[https://doi.org/10.3389/fspas.2022.829288\|Ionize Hard: Interstellar PO<sup>+</sup> Detection]]\\
		+	//Front. Astron. Space Sci.// 9, Art. No. 829288 (2022).\\
		+	In the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes, the //J// = 2 – 1 transition of NO<sup>+</sup> near 238.4 GHz was idenitified. Even though still only one transition has been detected, the identification may be more plausible now. The NO<sup>+</sup> to NO ratio was determined as 0.00245 ± 0.00005, very similar to the ratio in the report above. The preferred SO<sup>+</sup> to SO ratio in G+0.693−0.027 is 0.0045 ± 0.0003, quite similar, whereas the PO<sup>+</sup> to PO ratio was 0.12 ± 0.03.

-	----

-	Contributor(s): H. S. P. Müller; 10, 2014	+	----

		+	Contributor(s): H. S. P. Müller; 10, 2014; 05, 2022

	----		----

ns-plus

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Feb 2019 21:38:47 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Thionitrosylium, NS+, in Space =====
	+
	+	J. Cernicharo, B. Lefloch, M. Agúndez, S. Bailleux, L. Margulès, E. Roueff, R. Bachiller, N. Marcelino, B. Tercero, C. Vastel, and E. Caux\\
	+	reported on the\\
	+	[[https://doi.org/10.3847/2041-8213/aaa83a\|Discovery of the Ubiquitous Cation NS<sup>+</sup> in Space Confirmed by Laboratory Spectroscopy]]\\
	+	//Astrophys. J.// 853, Art. No. L22 (2018).\\
	+	The //J// = 2 – 1, 3 – 2, and 5 – 4 transitions of the closed shell thionitrosylium molecule near 100.2, 150.3, and 250.5 GHz were observed in emission with the IRAM 30 m telecope in the course of a molecular line survey of the dark cloud-type source B1b. The //J// = 2 – 1 transition was also observed in numerous other sources ranging from dark clouds, such as TMC-1 and L483, to low-mass protostars, such as NGC 1333 IRAS4A. It was not detected in the Orion KL hot core or compact ridge positions nor in the Sgr B2(M) or (N) hot cores. It was, however, detected in the envelope of Sgr B2. The cation is very abundant relative to the neutral (a NS/NS<sup>+</sup> ratio in the range of 30 to 50 was determined wherever possible) compared to other diatomics.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller 02, 2018
	+
	+
	+	----
	+

ns

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:53:13 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Nitrogen Sulfide, NS, in Space =====
	+
	+	The two Λ components of the //J// = 5/2 – 3/2 pertaining to the lower energy Π<sub>1/2</sub> ladder were detected with the NRAO 11 m telescope between 115 and 116 GHz toward Sgr B2(OH) by:\\
	+	C. A. Gottlieb, J. A. Ball, E. W. Gottlieb, C. J. Lada, and H. Penfield,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1975ApJ...200L.147G\|Detection of Interstellar Nitrogen Sulfide]]\\
	+	//Astrophys. J.// 200, L147–L149 (1975).\\
	+	The features displayed partially resolved hyperfine structure. The molecules was also detected in this and other transitions toward several other hot cores.
	+
	+	NS was also observed in TMC-1 and L134 by:\\
	+	D. McGonagle, W. M. Irvine, and M. Ohishi,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1994ApJ...422..621M\|Nitrogen Sulfide in Quiescent Dark Clouds]]\\
	+	//Astrophys. J.// 422, 621–625 (1994).
	+
	+	It has been detected in a planetary nebula:\\
	+	C. Sánchez Contreras, V. Bujarrabal, R. Neri, and J. Alcolea,\\
	+	[[https://ui.adsabs.harvard.edu/abs/2000A%26A...357..651S\|High-resolution observations at λ = 3 mm of the OH231.8+4.2 molecular outflow]]\\
	+	//Astron. Astrophys.// 357, 651–660 (2000).
	+
	+	NS occurs in PDRs as well:\\
	+	S. Leurini, R. Rolffs, S. Thorwirth, B. Parise, P. Schilke, C. Comito, F. Wyrowski, R. Güsten, P. Bergman, K. M. Menten, and L.-Å. Nyman,\\
	+	[[https://doi.org/10.1051/0004-6361:20065555\|APEX 1 mm Line Survey of the Orion Bar]]\\
	+	//Astron. Astrophys.// 454, L47–L50 (2006).
	+
	+	N<sup>34</sup>S has been identified tentative in Sgr B2(OH) by:\\
	+	B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989ApJS...70..539T\|A molecular line survey of Sagittarius B2 and Orion-KL from 70 to 115 GHz. I - The observational data]]\\
	+	//Astrophys. J. Suppl. Ser.// 70, 539–622 (1989).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller 08, 2011
	+
	+
	+	----
	+

o2

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:01:18 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== O2 in the Interstellar Medium =====
	+
	+	The //N<sub>J</sub>// = 3<sub>3</sub> – 1<sub>2</sub> line of molecular oxygen at 487249.270 (30) MHz has been detected tentatively with the SWAS satellite:\\
	+	P. F. Goldsmith, D. Li, E. A. Bergin, G. J. Melnick, V. Tolls, J. E. Howe, R. L. Snell, and D. A. Neufeld,\\
	+	[[https://doi.org/10.1086/341809\|Tentative Detection of Molecular Oxygen in the ρ Ophiuchi Cloud]]\\
	+	//Astrophys. J.// 576, 814–831 (2002).\\
	+	A column density of 3.17 (62) × 10<sup>16</sup>cm<sup>–2</sup> was derived. Since the column density of H<sub>2</sub> is rather uncertain, the fractional abundances of O<sub>2</sub> with respect to H<sub>2</sub> should be compared with great caution.\\
	+	Since this is the only putative O<sub>2</sub> line that has been observed, this detection should be viewed with great caution ! Moreover, the line occurs at a local standard of rest velocity of 6.0 km s<sup>–1</sup>, almost 3 km s<sup>–1</sup> different from that of many other molecules. This deviation corresponds to more than 4 MHz !\\
	+	At any rate, the study demonstrates an amount of O<sub>2</sub> in the ISM that is considerably lower than predicted by most models. The amount would drop even more should the detected line turn out to be not due to O<sub>2</sub>.
	+
	+	More recently, the //N<sub>J</sub>// = 1<sub>1</sub> – 1<sub>0</sub> line at 118750.340 (7) MHz was reported as a 5σ line toward the same source:\\
	+	B. Larsson, R. Liseau, L. Pagani, P. Bergman, P. Bernath, N. Biver, J. H. Black, R. S. Booth, V. Buat, J. Crovisier, C. L. Curry, M. Dahlgren, P. J. Encrenaz, E. Falgarone, P. A. Feldman, M. Fich, H. G. Florén, M. Fredrixon, U. Frisk, G. F. Gahm, M. Gerin, M. Hagström, J. Harju, T. Hasegawa, Å. Hjalmarson, L. E. B. Johansson, K. Justtanont, A. Klotz, E. Kyrölä, S. Kwok, A. Lecacheux, T. Liljeström, E. J. Llewellyn, S. Lundin, G. Mégie, G. F. Mitchell, D. Murtagh, L. H. Nordh, L.-Å. Nyman, M. Olberg, A. O. H. Olofsson, G. Olofsson, H. Olofsson, G. Persson, R. Plume, H. Rickman, I. Ristorcelli, G. Rydbeck, A. A. Sandqvist, F. V. Schéele, G. Serra, S. Torchinsky, N. F. Tothill, K. Volk, T. Wiklind, C. D. Wilson, A. Winnberg, and G. Witt,\\
	+	[[https://doi.org/10.1051/0004-6361:20065500\|Molecular Oxygen in the ρ Ophiuchi Cloud]]\\
	+	//Astron. Astrophys.// 466, 999–1003 (2007).\\
	+	The observations were carried out with the //Odin// satellite. A column density of 1 × 10<sup>15</sup>cm<sup>–2</sup> was derived, considerably lower than in the paper above. This indicates that the 487 GHz line is very likely caused by a different, currently unknown species. The relative abundance to H<sub>2</sub> is, as rather commonly, very uncertain. It has been estimated as 5 × 10<sup>–8</sup>. As this is the only O<sub>2</sub> line that has been observed with some certainty, the detection of O<sub>2</sub> should still be viewed with a bit of caution.
	+
	+	A total of three lines, //N<sub>J</sub>// = 3<sub>3</sub> – 1<sub>2</sub>, 5<sub>4</sub> – 3<sub>4</sub>, and 7<sub>6</sub> – 5<sub>6</sub>, at 487249.264 (17), 773839.512 (48), and 1120714.821 (31) MHz, respectively, were recently reported by:\\
	+	P. F. Goldsmith, R. Liseau, T. A. Bell, J. H. Black, J.-H. Chen, D. Hollenbach, M. J. Kaufman, D. Li, D. C. Lis, G. Melnick, D. Neufeld, L. Pagani, R. Snell, A. O. Benz, E. Bergin, S. Bruderer, P. Caselli, E. Caux, P. Encrenaz, E. Falgarone, M. Gerin, J. R. Goicoechea, Å. Hjalmarson, B. Larsson, J. Le Bourlot, F. Le Petit, M. De Luca, Z. Nagy, E. Roueff, A. Sandqvist, F. van der Tak, E. F. van Dishoeck, C. Vastel, S. Viti, and U. Yildiz,\\
	+	[[https://doi.org/10.1088/0004-637X/737/2/99\|//Herschel// Measurements of Molecular Oxygen in Orion]]\\
	+	//Astrophys. J.// 737, Art. No. 96 (2011).\\
	+	Even though the telescope was pointed toward the H<sub>2</sub> Peak 1 position with emission lines much weaker in most cases than in the Hot Core region and some 27" away from it, the LSR velocity seems to suggest an association with a region called "Peak A" in the course of ammonia observations in 1983, and it is just outside the Hot Core region. The region is likely warm, 80 to 100 K, possibly even warmer. A column density of 6.5 (10) × 10<sup>16</sup>cm<sup>–2</sup> was derived. The estimate of the abundance relative to H<sub>2</sub> was of order of 10<sup>–6</sup>. Warm dust, rather than shocks, were inferred to explain the fairly high abundance.
	+
	+	R. Liseau, P. F. Goldsmith, B. Larsson, L. Pagani, P. Bergman, J. Le Bourlot, T. A. Bell, A. O. Benz, E. A. Bergin, P. Bjerkeli, J. H. Black, S. Bruderer, P. Caselli, E. Caux, J.-H. Chen, M. de Luca, P. Encrenaz, E. Falgarone, M. Gerin, J. R. Goicoechea, Å. Hjalmarson, D. J. Hollenbach, K. Justtanont, M. J. Kaufman, F. Le Petit, D. Li, D. C. Lis, G. J. Melnick, Z. Nagy, A. O. H. Olofsson, G. Olofsson, E. Roueff, Aa. Sandqvist, R. L. Snell, F. F. S. van der Tak, E. F. van Dishoeck, C. Vastel, S. Viti, and U. A. Yildiz,\\
	+	reported on,\\
	+	[[https://doi.org/10.1051/0004-6361/201118575\|Multi-line Detection of O<sub>2</sub> toward ρ Ophuichi A]]\\
	+	//Astron. Astrophys.// 541, Art. No. A73 (2012).\\
	+	The HIFI instrument on board of the //Herschel// satellite was usd to study lines at 487.2 GHz and at 773.8 GHz. This investigation extends the one performed with the Odin satellite mentioned above and secures that identification.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2003; 02, 2006; 04, 2007; 08, 2011; 05, 2012
	+
	+	----
	+

oh-plus

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:10:26 +0000

other_c6h2

anonymous@undisclosed.example.com (Anonymous) — Thu, 17 Nov 2022 12:05:41 +0000

2022/11/17 12:47		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202245018\|Discovery of Two New Interstellar Molecules with QUIJOTE: HCCCHCCC and HCCCCS]]\\		[[https://doi.org/10.1051/0004-6361/202245018\|Discovery of Two New Interstellar Molecules with QUIJOTE: HCCCHCCC and HCCCCS]]\\
	//Astron. Astrophys.// 667, Art. No. L4 (2022).\\		//Astron. Astrophys.// 667, Art. No. L4 (2022).\\
-		+	Ethnylbutatrienylidene was detected through 27 //a//-type transitions with //K<sub>a</sub>// ≤ 2 and 9 ≤ //J// ≤ 15 and good to reasonable signal-to-noise ratios in the course of a molecular line survey of the prototypical cold dark molecular cloud TMC-1 carried out with the Yebes 40 m radio telescope between 31.0 and 50.3 GHz.
		+	Ethnylbutatrienylidene is, after hexapentaenylidene, C<sub>6</sub>H<sub>2</sub>, and triacetlylene, the third C<sub>6</sub>H<sub>2</sub> isomer detected in space. Its abundance is about a factor of 1.6 higher than that of the slightly lower lying C<sub>6</sub>H<sub>2</sub> molecule.\\
	\\		\\

oxiran

anonymous@undisclosed.example.com (Anonymous) — Fri, 09 Jun 2023 11:56:09 +0000

2023/06/09 13:54		current
Line 49:		Line 49:
	Five or six lines are essentially unblended and have a sufficient signal-to-noise ratio,		Five or six lines are essentially unblended and have a sufficient signal-to-noise ratio,
	two more lines are blended, and the combination of the contributions account nicely for the emission lines.		two more lines are blended, and the combination of the contributions account nicely for the emission lines.
-	So the identification was deemed to be somewhat tentative in this line-rich sourvey.	+	So the identification was deemed to be somewhat tentative in this line-rich survey.
	From the estimate of the column density, one can derive a degree of deuteration per H atom of ~0.16,		From the estimate of the column density, one can derive a degree of deuteration per H atom of ~0.16,
	compared to ~0.036 per H atom in the case of //c//-C<sub>2</sub>H<sub>3</sub>DO.		compared to ~0.036 per H atom in the case of //c//-C<sub>2</sub>H<sub>3</sub>DO.
	Such an enhancement of the degree of deuteration per H atom has also been seen for other		Such an enhancement of the degree of deuteration per H atom has also been seen for other
-	doubly deuterated molecules compared to the mono-deuerated varions, such as CHD<sub>2</sub>CN,	+	doubly deuterated molecules compared to their mono-deuerated variants, such as CHD<sub>2</sub>CN,
	CHD<sub>2</sub>OCHO, CH<sub>3</sub>OCHD<sub>2</sub>, CHD<sub>2</sub>OH, and CHD<sub>2</sub>CHO.\\		CHD<sub>2</sub>OCHO, CH<sub>3</sub>OCHD<sub>2</sub>, CHD<sub>2</sub>OH, and CHD<sub>2</sub>CHO.\\
	\\		\\

ph3

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:09:29 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On Phosphine, PH3 in Circumstellar Envelopes of Late-Type Stars =====
	+
	+	The detection of a circumstellar feature was tentatively attributed to the //J// = 1 – 0 transition of PH<sub>3</sub> by two groups almost simultaneously:\\
	+	E. D. Tenenbaum and L. M. Ziurys,\\
	+	[[https://doi.org/10.1086/589973\|A Search for Phosphine in Circumstellar Envelopes: PH<sub>3</sub> in IRC +10216 and CRL 2688 ?]]\\
	+	//Astrophys. J.// 680, L121–L124 (2008).\\
	+	M. Agúndez, J. Cernicharo, J. R. Pardo, M. Guélin, T. G. Phillips,\\
	+	[[https://doi.org/10.1051/0004-6361:200810193\|Tentative Detection of Phosphine in IRC +10216]]\\
	+	//Astron. Astrophys.// 485, L33–L36 (2008).\\
	+	The first work ascribed a feature at //v//<sub>LSR</sub> of the star to PH<sub>3</sub> close to the star. The second paper, however, convincingly assigned that feature to SiS in its //v// = 4 excited vibrational state. In the first work, the feature was not only detected in the envelope of the carbon-rich AGB star IRC +10216, but also in the protoplanetary nebula CRL 2688. The feature was also searched for in the protoplanetary nebula CRL 618, but was found to be overlapped by a line of HC<sub>3</sub>N in its //v//<sub>7</sub> = 4 excited vibrational state.
	+
	+	M. Agúndez, J. Cernicharo, L. Decin, P. Encrenaz, and D. Teyssier,\\
	+	reported recently on the\\
	+	[[https://doi.org/10.1088/2041-8205/790/2/L27\|Confirmation of Circumstellar Phosphine]]\\
	+	//Astrophys. J.// 790, Art. No. L27 (2014).\\
	+	The essentially overlapping //J// = 2 – 1, //K// = 0 and 1 transitions were observed in emission near 533.8 GHz with the //Herschel///HIFI instrument toward the famous carbon-rich AGB star CW Leonis, also known as IRC +10216.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2008; 07, 2014
	+
	+	----
	+

phcch

anonymous@undisclosed.example.com (Anonymous) — Wed, 27 Sep 2023 13:59:04 +0000

2023/09/27 15:44		current
Line 5:		Line 5:
	[[https://doi.org/10.1051/0004-6361/202347023\|Detection of ethynylbenzene in TMC-1 and the interstellar search for 1,2-diethynylbenzene]]\\		[[https://doi.org/10.1051/0004-6361/202347023\|Detection of ethynylbenzene in TMC-1 and the interstellar search for 1,2-diethynylbenzene]]\\
	//Astron. Astrophys.// 677, Art. No. A166 (2023).\\		//Astron. Astrophys.// 677, Art. No. A166 (2023).\\
		+	More than two dozen //a//-type transitions with 10 ≤ //J// ≤ 16 and //K<sub>a</sub>// ≤ 6 between 30.5 and 40.1 GHz were assigned as essentially unblended or only slightly blended transitions. The observations were part of the QUIJOTE line survey which covers 31.0 to 50.3 GHz and were carried out with the Yebes 40 m dish. The molecules is a factor of ~2.5 more abundant than cyanobenzene (aka benzonitrile). A similar ratio was reported for the ehynyl versus cyano derivatives of C<sub>3</sub>H<sub>4</sub>.\\
		+	\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 09, 2023
		+
		+	----

phcn

anonymous@undisclosed.example.com (Anonymous) — Tue, 13 Apr 2021 09:33:29 +0000

2019/02/25 22:38		current
Line 8:		Line 8:
	NRAO issued a [[https://public.nrao.edu/news/2018-gbt-chemistry/\|press release]] which was also issued by the CfA.\\		NRAO issued a [[https://public.nrao.edu/news/2018-gbt-chemistry/\|press release]] which was also issued by the CfA.\\
	The molecule was the most promising candidate for the detection of a benzene derived aromatic molecule by means of radio astronomy. Was it surprising that it was found in TMC-1 ?		The molecule was the most promising candidate for the detection of a benzene derived aromatic molecule by means of radio astronomy. Was it surprising that it was found in TMC-1 ?
		+
		+
		+	A. M. Burkhardt, R. A. Loomis, C. N. Shingledecker, K. L. K. Lee, A. J. Remijan, M. C. McCarthy, and B. A. McGuire\\
		+	reported on the\\
		+	[[https://doi.org/10.1038/s41550-020-01253-4\|Ubiquitous aromatic carbon chemistry at the earliest stages of star formation]]\\
		+	//Science// 359, 202–205 (2018).\\
		+	Benzonitrile was detected by the same method as in the first reference toward four additional dark clouds, Serpens 1A, 1B, 2, and L1521F.\\


	----		----

-	Contributor(s): H. S. P. Müller; 01, 2018	+	Contributor(s): H. S. P. Müller; 01, 2018; 04, 2021

phenalene

anonymous@undisclosed.example.com (Anonymous) — Wed, 18 Feb 2026 12:29:50 +0000

2026/02/18 13:16		current
Line 1:		Line 1:
-	===== On the Detection of Phenalene, C13H10, in the ISM =====	+	===== On the Detection of Phenalene, c-C13H10, in the ISM =====

	C. Cabezas, M. Agúndez, C. Pérez, D. Villar-Castro, G. Molpeceres, D. Pérez, A. L. Steber, R. Fuentetaja, B. Tercero, N. Marcelino, A. Lesarri, P. de Vicente, and J. Cernicharo\\		C. Cabezas, M. Agúndez, C. Pérez, D. Villar-Castro, G. Molpeceres, D. Pérez, A. L. Steber, R. Fuentetaja, B. Tercero, N. Marcelino, A. Lesarri, P. de Vicente, and J. Cernicharo\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1051/0004-6361/202556687\|Discovery of Interstellar Phenalene (//c//-C13H10): A new Piece in the Chemical Puzzle of PAHs in Space]]\\	+	[[https://doi.org/10.1051/0004-6361/202556687\|Discovery of Interstellar Phenalene (c-C13H10): A new Piece in the Chemical Puzzle of PAHs in Space]]\\
	//Astron. Astrophys.// 701, Art. No. L8 (2025).\\		//Astron. Astrophys.// 701, Art. No. L8 (2025).\\
	Phenalene was identified through several //a//-type rotational transitions, often series easier to detect because of oblate pairing of the transitions having the same //K<sub>c</sub>// close to //J// and then blended with weaker //b//-type transitions having equivalent quantum numbres. Some isolated //b//-type transitions were also assigned in the astronomical spectrum. The identifications were based on the QUIJOTE molecular line survey carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz, but phenalene assignments were made only up to 39.8 GHz. A rotational temperature of 8 K was derived. The column density of phenalene appears to be slightly larger than that of the lighter indene, albeit with considerable uncertainty.\\		Phenalene was identified through several //a//-type rotational transitions, often series easier to detect because of oblate pairing of the transitions having the same //K<sub>c</sub>// close to //J// and then blended with weaker //b//-type transitions having equivalent quantum numbres. Some isolated //b//-type transitions were also assigned in the astronomical spectrum. The identifications were based on the QUIJOTE molecular line survey carried out with the Yebes 40 m radio telescope between 31.0 and 50.4 GHz, but phenalene assignments were made only up to 39.8 GHz. A rotational temperature of 8 K was derived. The column density of phenalene appears to be slightly larger than that of the lighter indene, albeit with considerable uncertainty.\\

pn

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:54:17 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detections of Phosphorus Nitride, PN, in Space =====
	+
	+	B. E. Turner and J. Bally\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987ApJ...321L..81Z\|Detection of Interstellar PN – The First Identified Phosphorus Compound in the Interstellar Medium]]\\
	+	//Astron. Astrophys.// 321, L75–L79 (1987).\\
	+	The //J// = 2 – 1, 3 – 2, and 5 –&nbsp4; transitions were detected with the NRAO 12 m and BTL 7 m telescopes in emission near 94.0, 141.0, and 234.9 GHz. The lines were detected in the high-mass star-forming regions Orion KL, W51M, and Sgr B2.
	+
	+	L. M. Ziurys, S. N. Milam, A. J. Apponi, and N. J. Woolf\\
	+	reported on\\
	+	[[https://doi.org/10.1038/nature05905\|Chemical Complexity in the Winds of the Oxygen-rich Supergiant Star VY Canis Majoris]]\\
	+	//Nature// 447, 1094–1097 (2007).\\
	+	PN was identified in the course of a molecular line survey with the ARO 12 m and the SMT 10 m telescopes, covering large sections of the 75–270 GHz region.
	+
	+	S. N. Milam, D. T. Halfen, E. D. Tenenbaum, A. J. Apponi, N. J. Woolf, and L. M. Ziurys\\
	+	reported on\\
	+	[[https://doi.org/10.1086/589135\|Constraining Phosphorus Chemistry in Carbon- and Oxygen-Rich Circumstellar Envelopes: Observations of PN, HCP, and CP]]\\
	+	//Astrophys. J.// 684, 618–625 (2008).\\
	+	Several lines of PN were detected with the same instruments as above toward the envelopes of the carbon-rich late-type stars V1610 Cygni (aka CRL 2688) and CW Leonis (aka IRC +10216).
	+
	+	PN was also detected around a (low-mass) class 0 proto-star:\\
	+	[[https://doi.org/10.1093/pasj/63.5.L37\|Detection of Phosphorus Nitride in the Lynds 1157 B1 Shocked Region]]\\
	+	by T. Yamaguchi, S. Takano, N. Sakai, T. Sakai, S.-Y. Liu, Y.-N. Su, N. Hirano, S. Takakuwa, Y. Aikawa, H. Nomura, and S. Yamamoto,\\
	+	//Publ. Astron. Soc. Japan// 63, L37–L41 (2011).\\
	+	The //J// = 2 – 1 transition near 94.0 GHz was detected in emission with the Nobeyama 45 m telescope in the course of a molecular line survey covering the 3 mm region.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 08; 2016
	+
	+
	+	----
	+

po-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 25 May 2022 13:57:11 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of PO+ in Space =====
	+
	+	V. M. Rivilla, J. G. De La Concepción, I. Jiménez-Serra, J. Martín-Pintado, L. Colzi, B. Tercero, A. Megías, Á. López-Gallifa, A. Martínez-Henares, S. Massalkhi, S. Martín, S. Zeng, P. De Vicente, F. Rico-Villas, M. A. Requena-Torres, and G. Cosentino\\
	+	announced\\
	+	[[https://doi.org/10.3389/fspas.2022.829288\|Ionize Hard: Interstellar PO<sup>+</sup> Detection]]\\
	+	//Front. Astron. Space Sci.// 9, Art. No. 829288 (2022).\\
	+	The //J// = 1 – 0 and 2 – 1 transitions of this closed shell cation near 47.0 and 94.0 GHz were identified in emission in the course of a molecular line survey of the Galactic center cold molecular cloud G+0.693−0.027 carried out with the Yebes 40 m and IRAM 30 m radio telescopes. An excitation temperature of 4.5 K was taken from PN; this value was also used for the neutral PO radical. The PO<sup>+</sup> to PO ratio was 0.12 ± 0.03, much higher than the preferred SO<sup>+</sup> to SO ratio of 0.0045 ± 0.0003 or the NO<sup>+</sup> to NO ratio of 0.00245 ± 0.00005.\\
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2022
	+
	+	----

po

anonymous@undisclosed.example.com (Anonymous) — Wed, 21 Aug 2024 14:33:02 +0000

2024/08/21 16:20		current
Line 29:		Line 29:
	\\		\\

-		+	S. H. J. Wallström, T. Danilovich, H. S. P. Müller, C. A. Gottlieb, S. Maes, M. Van de Sande, L. Decin, A. M. S. Richards, A. Baudry, J. Bolte, T. Ceulemans, F. De Ceuster, A. de Koter, I. El Mellah, M. Esseldeurs, S. Etoka, D. Gobrecht, E. Gottlieb, M. Gray, F. Herpin, M. Jeste, D. Kee, P. Kervella, T. Khouri, E. Lagadec, J. Malfait, L. Marinho, I. McDonald, K. M. Menten, T. J. Millar, M. Montargès, J. A. Nuth, J. M. C. Plane, R. Sahai, L. B. F. M. Waters, K. T. Wong, J. Yates, and A. Zijlstra\\
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/202347632\|ATOMIUM: Molecular Inventory of 17 Oxygen-rich Evolved Stars Observed with ALMA]]\\
		+	//Astron. Astrophys.// 681, Art. No. A50 (2024).\\
		+	The authors detect in their ALMA measurements in Band 6 vibrationally excited PO toward AH Sco, IRC+10011, IRC−10529,
		+	R Hya, and S Pav. The Ω = 3/2, //J// = 11/2 − 9/2, //F// = 6 − 5 and 5 − 4 lines near 239.9 GHz with unresolved Λ-doubling were detected near the //v// = 0, Ω = 1/2, //J// = 11/2 − 9/2, //F// = 6 − 5 and 5 − 4 //e//-lines near 240.0 GHz; the //f//-lines were not covered.\\
		+	\\

	----		----

prcn

anonymous@undisclosed.example.com (Anonymous) — Tue, 28 Jun 2022 14:54:57 +0000

2020/09/18 14:08		current
Line 13:		Line 13:
	[[molecules:ism:aan\|Aminoacetonitrile]] was detected earlier in the course of this molecular line survey. At a rotational temperature of about 150 K, very many transitions of //n//-propyl cyanide have non-negligible intensities. However, many of them are blended severely with emissions or absorptions of other molecules. Nevertheless, a considerable number of transitions of the lower energy //anti//-conformer are not or only slightly blended. Its column density is about a factor of 100 lower in Sgr B2(N) than those of methyl and ethyl cyanide.		[[molecules:ism:aan\|Aminoacetonitrile]] was detected earlier in the course of this molecular line survey. At a rotational temperature of about 150 K, very many transitions of //n//-propyl cyanide have non-negligible intensities. However, many of them are blended severely with emissions or absorptions of other molecules. Nevertheless, a considerable number of transitions of the lower energy //anti//-conformer are not or only slightly blended. Its column density is about a factor of 100 lower in Sgr B2(N) than those of methyl and ethyl cyanide.

-	//n//-Propyl cyanide is the third alkyl cyanide to be detected in space after methyl cyanide, [[molecules:ism:mecn\|CH<sub>3</sub>CN]], and ethyl cyanide, [[molecules:ism:etcn\|C<sub>2</sub>H<sub>5</sub>CN]].	+	//n//-Propyl cyanide is the third alkyl cyanide to be detected in space after methyl cyanide, [[molecules:ism:mecn\|CH<sub>3</sub>CN]], and ethyl cyanide, [[molecules:ism:etcn\|C<sub>2</sub>H<sub>5</sub>CN]].

	Transitions of the lower energy //g//-//n//-propyl cyanide were detected unambiguously in the course of a line survey of the same region carried out with ALMA which lead to the detection of //i//-propyl cyanide as described in the paragraphs further below.\\		Transitions of the lower energy //g//-//n//-propyl cyanide were detected unambiguously in the course of a line survey of the same region carried out with ALMA which lead to the detection of //i//-propyl cyanide as described in the paragraphs further below.\\
Line 30:		Line 30:
	[[https://doi.org/10.1126/science.1256678\|Detection of a Branched Alkyl Molecule in the Interstellar Medium: //iso//-Propyl Cyanide]]\\		[[https://doi.org/10.1126/science.1256678\|Detection of a Branched Alkyl Molecule in the Interstellar Medium: //iso//-Propyl Cyanide]]\\
	//Science// 345, (2014) 1584–1587.\\		//Science// 345, (2014) 1584–1587.\\
-	See also the [[https://www.mpifr-bonn.mpg.de/pressreleases/2014/10\|MPIfR press release]] (in English; German version also available) or the [[https://portal.uni-koeln.de/universitaet/aktuell/presseinformationen/detail/interstellare-molekuele-verzweigen-sich\|Universität zu Köln press release]] (in German).	+	See also the [[https://www.mpifr-bonn.mpg.de/pressreleases/2014/10\|MPIfR press release]] (in English; [[https://www.mpifr-bonn.mpg.de/pressemeldungen/2014/10\|German version]] also available) or the [[https://portal.uni-koeln.de/universitaet/aktuell/presseinformationen/detail/interstellare-molekuele-verzweigen-sich\|Universität zu Köln press release]] (in German).

	The molecule is the first one found in the interstellar medium with a branched carbon backbone. It is a first step towards confirming earlier assumptions that branched molecules are abundant in space. This is a particularly important finding for the search for amino acids and other biogenic molecules in space. The molecule is also the fourth alkyl cyanide found in space.		The molecule is the first one found in the interstellar medium with a branched carbon backbone. It is a first step towards confirming earlier assumptions that branched molecules are abundant in space. This is a particularly important finding for the search for amino acids and other biogenic molecules in space. The molecule is also the fourth alkyl cyanide found in space.

proh

anonymous@undisclosed.example.com (Anonymous) — Thu, 04 Aug 2022 09:53:06 +0000

2022/06/28 17:03		current
Line 11:		Line 11:
	reported on\\		reported on\\
	[[https://doi.org/10.1051/0004-6361/202142699\|Precursors of Fatty Alcohols in the ISM: Discovery of //n//-Propanol]]\\		[[https://doi.org/10.1051/0004-6361/202142699\|Precursors of Fatty Alcohols in the ISM: Discovery of //n//-Propanol]]\\
-	//Astron. Astrophys.//, (2022), in press.\\	+	//Astron. Astrophys.// 663 (2022), Art. No. A181.\\
-	Transitions of the //Ga// and //Aa// conformers of 1-propanol were observed in the course of a molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius (Sgr) B2(N) carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3, 2, and 1 mm. The identified transitions cover the 2 to 7 mm regions 2 ≤ //J// ≤ 11 and //K<sub>a</sub>// ≤ 6 for //Ga// and 2 ≤ //J// ≤ 12 and //K<sub>a</sub>// ≤ 3 for //Aa//. The number of clean, slightly or partly blended transitions is sufficiently large for both conformers together and for //Ga// alone. The excitation temperature is about 13 K. //n//-Propanol is about a factor of 15 less abundant than ethanol which, in turn, is about a factor of 25 less abundant than methanol.\\	+	Transitions of the //Ga// and //Aa// conformers of 1-propanol were observed in the course of molecular line surveys of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius (Sgr) B2(N) carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3, 2, and 1 mm. The identified transitions cover the 2 to 7 mm regions 2 ≤ //J// ≤ 11 and //K<sub>a</sub>// ≤ 6 for //Ga// and 2 ≤ //J// ≤ 12 and //K<sub>a</sub>// ≤ 3 for //Aa//. The number of clean, slightly or partly blended transitions is sufficiently large for both conformers together and for //Ga// alone. The excitation temperature is about 13 K. //n//-Propanol is about a factor of 15 less abundant than ethanol which, in turn, is about a factor of 25 less abundant than methanol.\\
	\\		\\

propin

anonymous@undisclosed.example.com (Anonymous) — Mon, 14 Jun 2021 13:14:08 +0000

2021/06/14 15:08		current
Line 76:		Line 76:
	M. Agúndez, E. Roueff, C. Cabezas, J. Cernicharo, and N. Marcelino\\		M. Agúndez, E. Roueff, C. Cabezas, J. Cernicharo, and N. Marcelino\\
	reported on the\\		reported on the\\
-	[[https://doi.org/10.1086/432415\|First detection of doubly deuterated methyl acetylene (CHD<sub>2</sub>CCH and CH<sub>2</sub>DCCD)]]\\	+	[[https://doi.org/10.1051/0004-6361/202140843\|First detection of doubly deuterated methyl acetylene (CHD<sub>2</sub>CCH and CH<sub>2</sub>DCCD)]]\\
	//Astron. Astrophys.// 649, Art. No. A 171 (2021).\\		//Astron. Astrophys.// 649, Art. No. A 171 (2021).\\
-	The identifications were made in the course of a molecular line survey of L483 at 3 mm carried out with the IRAM 30 m radio telescope. The survey samples cold material; the presence of the embedded Class 0 infrared source IRAS 18148−0440 is not visible in these data. 9 and 8 //a//-type transition frequencies with 4 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 1 were reported. \\	+	The identifications were made in the course of a molecular line survey of L483 at 3 mm carried out with the IRAM 30 m radio telescope. The survey samples cold material; the presence of the embedded Class 0 infrared source IRAS 18148−0440 is not visible in these data. 9 and 8 //a//-type transition frequencies with 4 ≤ //J// ≤ 7 and //K<sub>a</sub>// ≤ 1 were reported. The column density ratios of CH<sub>3</sub>CCH with CH<sub>2</sub>DCCH, CH<sub>3</sub>CCD, CHD<sub>2</sub>CCH, and CH<sub>2</sub>DCCD are about 5, 16, 34, and 42, respectively.\\

sh-plus

anonymous@undisclosed.example.com (Anonymous) — Wed, 14 Jul 2021 08:58:18 +0000

sh

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:12:22 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Sulfanyl, SH, in the Interstellar Medium =====
	+
	+	The //J// = 5/2 – 3/2 transition of the lower energy fine structure component <sup>2</sup>Π<sub>3/2</sub> of the sulfanyl radical SH has been detected in absorption in the diffuse medium along the sight-line to the submillimeter continuum source W49N by\\
	+	D. A. Neufeld, E. Falgarone, M. Gerin, B. Godard, E. Herbst, G. Pineau des Forêts, A. I. Vasyunin, R. Güsten, H. Wiesemeyer, and O. Ricken,\\
	+	[[https://doi.org/10.1051/0004-6361/201218870\|Discovery of Interstellar Mercapto Radicals (SH) with the GREAT Instrument on SOFIA]]\\
	+	//Astron. Astrophys.// 542, (2012), Art. No. L6.\\
	+	Two lines were observed near 1382.91 and 1383.24 GHz because of the Λ-doubling. The inferred column density is very similar to that of SH<sup>+</sup> in that source, differing by less than a factor of two.
	+
	+	D. A. Neufeld, B. Godard, M. Gerin, G. Pineau des Forêts, C. Bernier, E. Falgarone, U. U. Graf, R. Güsten, E. Herbst, P. Lesaffre, P. Schilke, P. Sonnentrucker, and H. Wiesemeyer\\
	+	reported on\\
	+	[[https://doi.org/10.1051/0004-6361/201425391\|Sulphur-bearing molecules in diffuse molecular clouds: new results from SOFIA/GREAT and the IRAM 30 m telescope]]\\
	+	//Astron. Astrophys.// 577, (2015), Art. No. A49.\\
	+	The same transitions of SH as above were observed toward W31C, G29.96-0.02, G34.3+0.1, W51, and W49N again.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2012; 12, 2015.
	+
	+
	+	----
	+

si2c

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:41:30 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Circumstellar Si2C =====
	+
	+	Si<sub>2</sub>C, because of the two SiC single bonds best described as disilylidynemethylene, but also known as dislicon carbide, is a bent molecule. Together with SiC<sub>2</sub>, it was predicted to be very abundant in the circumstellar envelopes of C-rich late type stars. Its fairly small dipole moment as well as its not so favorable structure prevented its rotational spectrum to be recorded in the laboratory and in space until very recently.\\
	+	J. Cernicharo, M. C. McCarthy, C. A. Gottlieb, M. Agúndez, L. Velilla-Prieto, J. H. Baraban, P. B. Changala, M. Guélin, C. Kahane, M. A. Martin-Drumel, N. A. Patel, N. J. Reilly, J. F. Stanton, G. Quintana-Lacaci, S. Thorwirth, and K. H. Young,\\
	+	reported on the\\
	+	[[https://doi.org/10.1088/2041-8205/806/1/L3\|Discovery of SiCSi in IRC+10216: A Missing Link between Gas and Dust Carriers of Si–C Bonds]]\\
	+	//Astrophys. J.// 806, Art. No. L3 (2015).\\
	+	More than hundred lines between 82 and 351 GHz were detected toward CW Leonis with the IRAM 30 m telescope.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2015
	+
	+
	+	----
	+

sic_2n_1

anonymous@undisclosed.example.com (Anonymous) — Tue, 03 Feb 2026 09:25:27 +0000

2025/09/02 17:07		current
Line 1:		Line 1:
	===== On SiC<sub>2n+1</sub> (n ≥ 1) Radicals around CW Leonis =====		===== On SiC<sub>2n+1</sub> (n ≥ 1) Radicals around CW Leonis =====

-	J. Cernicharo, J. R. Pardo, M. Agúndez, J. P. Fonfría, L. Velilla-Prieto, C. Cabezas, B. Tercero, P. de Vicente and M. Guélin \\	+	J. Cernicharo, J. R. Pardo, M. Agúndez, J. P. Fonfría, L. Velilla-Prieto, C. Cabezas, B. Tercero, P. de Vicente and M. Guélin \\
	announced\\		announced\\
	[[https://doi.org/10.1051/0004-6361/202556370\|Detection of the linear SiC3 and SiC5 radicals in IRC+10216]]\\		[[https://doi.org/10.1051/0004-6361/202556370\|Detection of the linear SiC3 and SiC5 radicals in IRC+10216]]\\
	//Astron. Astrophys.// 700, Art. No. L20 (2025).\\		//Astron. Astrophys.// 700, Art. No. L20 (2025).\\
	Propadienediylidenesilylene and pentatetraenediylidenesilylene, which are also known as silatetratrienediylidene and silahexapentaenediylidene, respectively, were detercted in their <sup>3</sup>Σ<sup>−</sup> ground electronic states in the envelopes of the prototypical carbon-rich late-type AGB star CW Leonis in the course of a molecular line survey in the 31.0 to 50.3 GHz region carried out with the 40 m Yebes telescope.		Propadienediylidenesilylene and pentatetraenediylidenesilylene, which are also known as silatetratrienediylidene and silahexapentaenediylidene, respectively, were detercted in their <sup>3</sup>Σ<sup>−</sup> ground electronic states in the envelopes of the prototypical carbon-rich late-type AGB star CW Leonis in the course of a molecular line survey in the 31.0 to 50.3 GHz region carried out with the 40 m Yebes telescope.
-	In the case of propadienediylidenesilylene (SiC<sub>3</sub>), all three strong fine structure (FS) components with Δ//J// = Δ//N// of the four transitions with 5 ≤ //N// ≤ 9 were covered. Two FS components were heavily blended, the other ones unblended or partially blended, though the ones pertaining to the highest //N// have a rather modest signal-to-noise ratio. In the case of pentatetraenediylidenesilylene (SiC<sub>5</sub>), FS components of transitions with 16 ≤ //N// ≤ 25 were covered. While several of them are severely blended, sufficiently many are unblended or partially blended. The values of //T//<sub>rot</sub> were estimated as ~5 and ~17 K for SiC<sub>3</sub> and SiC<sub>5</sub>, respectively. The abundance ratios of the prolate rhomboidal (bicyclic) SiC<sub>3</sub> to the linear forms of SiC<sub>3</sub> and SiC<sub>5</sub> are about 4 : 2 : 1, where the value of the first species refers to a fit with two temperature components. \\	+	In the case of propadienediylidenesilylene (SiC<sub>3</sub>), all three strong fine structure (FS) components with Δ//J// = Δ//N// of the four transitions with 5 ≤ //N// ≤ 9 were covered. Two FS components were heavily blended, the other ones unblended or partially blended, though the ones pertaining to the highest //N// have a rather modest signal-to-noise ratio. In the case of pentatetraenediylidenesilylene (SiC<sub>5</sub>), FS components of transitions with 16 ≤ //N// ≤ 25 were covered. While several of them are severely blended, sufficiently many are unblended or partially blended. The values of //T//<sub>rot</sub> were estimated as ~5 and ~17 K for SiC<sub>3</sub> and SiC<sub>5</sub>, respectively. The abundance ratios of the prolate rhomboidal (bicyclic) SiC<sub>3</sub> to the linear forms of SiC<sub>3</sub> and SiC<sub>5</sub> are roughly 4 : 2 : 1. Similar values are obtained if instead of rhomboidal SiC<sub>3</sub> (linear) SiC<sub>4</sub> is taken.\\
	\\		\\

sic

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:49:39 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Circumstellar Silicon Carbide, SiC =====
	+
	+	Silicon carbide, SiC, has an inverted <sup>3</sup>Π ground electronic state. The low-lying Ω = 2 component shows negligible Λ-doubling. The Ω = 1 and 0 components are about 60 amd 120 K higher in energy, respectively, and show substantial Λ-doubling.\\
	+	SiC has been detected thus far only in the circumstellar envelope of CW Leo, also known as IRC +10216. 3, 3, and 1 components were detected for the //J"// = 1, 3, and 5 transitions near 80, 160, and 240 GHz covering all fine structure components by\\
	+	J. Cernicharo, C. A. Gottlieb, M. Guélin, P. Thaddeus, and J. M. Vrtílek,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989ApJ...341L..25C\|Astonomical and Laboratory Detection of the SiC Radical]]\\
	+	//Astrophys. J.// 341, L25–L28 (1989).\\
	+	The molecule occurs further away from the star than SiS or SiC<sub>2</sub> as judged by the line shape. The excitation is probably far from LTE as the transitions within each fine structure component indicate a rotational temperature of around 13 K. In contrast, the relative intensities of the fine structure transitions suggest a temperature closer to 90 K.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 09, 2012
	+
	+
	+	----
	+

sic2

anonymous@undisclosed.example.com (Anonymous) — Tue, 23 Jan 2024 14:26:42 +0000

2024/01/23 15:14		current
Line 27:		Line 27:
	\\		\\

-	P. D. Gensheimer and L. E. Snyder,\\	+	P. D. Gensheimer and L. E. Snyder\\
		+	reported on\\
	[[https://doi.org/10.1086/304916\|A Search for Vibrationally Excited SiC<sub>2</sub> //v//<sub>3</sub> = 1 toward IRC +10216]]\\		[[https://doi.org/10.1086/304916\|A Search for Vibrationally Excited SiC<sub>2</sub> //v//<sub>3</sub> = 1 toward IRC +10216]]\\
	//Astrophys. J.// 490, 819–822 (1997);\\		//Astrophys. J.// 490, 819–822 (1997);\\
Line 33:		Line 34:

	Several transitions of SiC<sub>2</sub> //v//<sub>3</sub> = 2 were identified by\\		Several transitions of SiC<sub>2</sub> //v//<sub>3</sub> = 2 were identified by\\
-	N. A. Patel, K. H. Young, C. A. Gottlieb, P. Thaddeus, R. W. Wilson, K. M. Menten, M. J. Reid, M. C. McCarthy, J. Cernicharo, J. H. He, S. Brünken, D.-V. Trung, and E. Keto,\\	+	N. A. Patel, K. H. Young, C. A. Gottlieb, P. Thaddeus, R. W. Wilson, K. M. Menten, M. J. Reid,
		+	M. C. McCarthy, J. Cernicharo, J. H. He, S. Brünken, D.-V. Trung, and E. Keto,\\
	[[https://doi.org/10.1088/0067-0049/193/1/17\|An Interferometric Spectral-line Survey of IRC +10216 in the 345 GHz Band]]\\		[[https://doi.org/10.1088/0067-0049/193/1/17\|An Interferometric Spectral-line Survey of IRC +10216 in the 345 GHz Band]]\\
	//Astrophys. J. Suppl. Ser.// 193, Art. No. 17 (2011).\\		//Astrophys. J. Suppl. Ser.// 193, Art. No. 17 (2011).\\
	\\		\\

		+	S. Massalkhi, I. Jiménez-Serra, J. Martín-Pintado, V. M. Rivilla, L. Colzi, S. Zeng, S. Martín,
		+	B. Tercero, P. de Vicente, and M. A. Requena-Torres\\
		+	announced\\
		+	[[https://doi.org/10.1051/0004-6361/202346822\|The First Detection of SiC<sub>2</sub> in the Interstellar Medium]]\\
		+	//Astron. Astrophys.// 678, Art. No. A45 (2023).\\
		+	The molecule was detected in the course of a molecular line survey of the Galactic Center molecular cloud G+0.693–0.027 employing the Yebes 40 m and IRAM 30 m radio telecopes. The reported 6 //a//-type transitions, of which 4 were deemed to be unblended. The authors also identified SiS, <sup>29</sup>SiO, <sup>30</sup>SiO, Si<sup>18</sup>O, and SiO. The last molecule was optically thick, and its abundance was estimated from that of Si<sup>18</sup>O.\\
		+	\\


	----		----

-	Contributor(s): H. S. P. Müller; 03, 2011; 06, 2013	+	Contributor(s): H. S. P. Müller; 03, 2011; 06, 2013; 01, 2024

	----		----

sic3

anonymous@undisclosed.example.com (Anonymous) — Tue, 22 Oct 2019 15:07:59 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On SiC3 Isomers in Space =====
	+
	+	There are three SiC<sub>3</sub> isomers which have been studied in the laboratoy, two bicyclic, rhomboidal singlet isomers and a linear triplet species. The prolate bicyclic molecule, with a CC bond creating the bicyclus, is lowest in energy and was observed in space. The other two are considerably higher in energy.
	+
	+	A. J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus\\
	+	reported on the\\
	+	[[https://doi.org/10.1086/311998\|Astronomical Detection of Rhomboidal SiC<sub>3</sub>]]\\
	+	//Astrophys. J.// 516, L103–L106 (1999).\\
	+	7 emission lines of 9 rotational transitions with //J"// between 6 and 8 were detected in the circumstellar envelope of CW Leo (IRC +10216) with the 12 m NRAO telescope between 80 and 103 GHz.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 05, 2015
	+
	+	----
	+

sic6

anonymous@undisclosed.example.com (Anonymous) — Fri, 08 Aug 2025 13:47:39 +0000

2025/08/07 15:03		current
Line 1:		Line 1:
	===== On the Detection of Hexapentaenediylidenesilylene =====		===== On the Detection of Hexapentaenediylidenesilylene =====

-	J. R. Pardo, J. P. Fonfría, M. Agúndez, B. Tercero, C. Cabezas, L. Velilla-Prieto, M. Guélin, P. de Vicente, and J. Cernicharo\\	+	J. R. Pardo, J. P. Fonfría, M. Agúndez, B. Tercero, C. Cabezas, L. Velilla-Prieto, M. Guélin, P. de Vicente, and J. Cernicharo\\
	reported on the\\		reported on the\\
	[[https://doi.org/10.1051/0004-6361/202555902\|Detection of SiC<sub>6</sub> in IRC +10216 through //Q//-band lines]]\\		[[https://doi.org/10.1051/0004-6361/202555902\|Detection of SiC<sub>6</sub> in IRC +10216 through //Q//-band lines]]\\
	//Astron. Astrophys.// 700, L6 (2025).\\		//Astron. Astrophys.// 700, L6 (2025).\\
-	Hexapentaenediylidenesilylene, also known as silaheptahexaenediylidene, was detected in a line survey of CW Leonis in the 31.0 to 50.3 GHz region carried out with the 40 m Yebes telescope. 14 transitions with //J'// = 26 − 31 and 33 − 40 were covered with mostly good signal-to-noise ratio. Of these, 8 were not or only slightly blended and 2 were partly unblended. A rotational temperature of ~19 K was determined, in agreement with the more uncertain ~21 K determined for SiC<sub>4</sub>	+	Hexapentaenediylidenesilylene, also known as silaheptahexaenediylidene, was detected in a line survey of CW Leonis in the 31.0 to 50.3 GHz region carried out with the 40 m Yebes telescope. 14 transitions with //J'// = 26 − 31 and 33 − 40 were covered with mostly good signal-to-noise ratio. Of these, 8 were not or only slightly blended and 2 were partly unblended. A rotational temperature of ~19 K was determined, in agreement with the more uncertain ~21 K determined for SiC<sub>4</sub>. The latter molecule is almost a factor of 10 more abundant than SiC<sub>6</sub>.\\
		+	\\
		+
		+	----
		+
		+	Contributor(s): H. S. P. Müller; 08, 2025
		+
		+	----
		+

sicn_sinc

anonymous@undisclosed.example.com (Anonymous) — Mon, 21 Oct 2019 15:37:55 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== SiCN and SiNC in IRC+10216 =====
	+
	+	Cyanosilylidyne was identified in spectra recorded toward IRC+10216 by\\
	+	M. Guélin, S. Muller, J. Cernicharo, A. J. Apponi, M. C. McCarthy, C. A. Gottlieb, and P. Thaddeus,\\
	+	[[https://ui.adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2000A%26A...363L...9G\|Astronomical detection of the free radical SiCN]]\\
	+	//Astron. Astrophys.// 363, L9–L12 (2000).
	+
	+	According to //ab initio// calcultions, the isocyanosilylidyne isomer has a thermodynamic stability very similar to that of SiCN, but a slightly smaller dipole moment. Therefore, its reported detection was only a matter of time:\\
	+	M. Guélin, S. Muller, J. Cernicharo, M. C. McCarthy, and P. Thaddeus,\\
	+	[[https://doi.org/10.1051/0004-6361:200400074\|Detection of the SiNC Radical in IRC+10216]]\\
	+	//Astron. Astrophys.// 426, L49–L52 (2004).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 11, 2004
	+
	+	----
	+

sih

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 11:02:22 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Tentative Detection of Silylidyne =====
	+
	+	The tentative identification of silylidyne, SiH, toward Orion KL was reported by\\
	+	P. Schilke, D. J. Benford, T. R. Hunter, D. C. Lis, and T. G. Philips,\\
	+	[[https://doi.org/10.1086/318951\|A Line Survey of Orion-KL from 607 to 725 GHz]]\\
	+	//Astrophys. J. Suppl. Ser.// 132, 281–364 (2001).\\
	+	The two λ components of the //J// = 1.5 – 0.5 transition pertaining to the energetically lower lying Π<sub>1/2</sub> spin-state near 624.9 and 627.7 GHz were detected. However, they were at least partially overlapped. As the source is rather line rich, the detection was viewed as tentative.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 06, 2006
	+
	+	----
	+

sih3cn

anonymous@undisclosed.example.com (Anonymous) — Thu, 09 May 2019 10:42:36 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== On the Detection of Silyl Cyanide, SiH3CN, in Space =====
	+
	+	J. Cernicharo, M. Agúndez, L. Velilla Prieto, M. Guélin, J. R. Pardo, C. Kahane, C. Marka, C. Kramer, S. Navarro, G. Quintana-Lacaci, J. P. Fonfría, N. Marcelino, B. Tercero, E. Moreno, S. Massalkhi, M. Santander-García, M. C. McCarthy, C. A. Gottlieb, and J. L. Alonso\\
	+	reported on the\\
	+	[[https://doi.org/10.1051/0004-6361/201731672\|Discovery of Methyl Silane and Confirmation of Silyl Cyanide in IRC +10216]]\\
	+	//Astron. Astrophys.// 606, Art. No. L5 (2017).\\
	+	6 sets of silyl cyanide, SiH<sub>3</sub>CN, transitions with //J'// between 9 and 17 (between 89 and 170 GHz) were detected with the IRAM 30 m telescope in emission toward the late-type C-rich star CW Leonis. The //K// level structure is partly resolved. At least some degree of blending by emission lines of other molecules is present.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2017
	+
	+
	+	----
	+

sih4

anonymous@undisclosed.example.com (Anonymous) — Wed, 23 Oct 2019 15:14:36 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== The Detection of Silane, SiH4, in IRC +10216 =====
	+
	+	13 rovibrational transitions of the ν<sub>4</sub> band around 917 cm<sup>–1</sup> were recorded by\\
	+	D. M. Goldhaber and A. L. Betz,\\
	+	[[https://doi.org/10.1086/184255\|Silane in IRC +10216]],\\
	+	//Astrophys. J// 279 L55–L58 (1984).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 10, 2008
	+
	+	----
	+

sin

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:54:37 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== SiN in Space =====
	+
	+	Silicon nitride, SiN, was identified in spectra recorded toward IRC+10216 by\\
	+	B. E. Turner,\\
	+	[[https://doi.org/10.1086/186324\|Detection of SiN in IRC +10216]]\\
	+	//Astrophys. J.// 388, L35–L38 (1992).
	+
	+	SiN is one of the few silicon containing molecules that have been observed in the interstellar medium – in this case in absorption toward Sgr B2(M):\\
	+	P. Schilke, S. Leurini, K. M. Menten, and J. Alcolea,\\
	+	[[https://doi.org/10.1051/0004-6361:20031649\|Interstellar SiN]]\\
	+	//Astron. Astrophys.// 412, L15–L18 (2003).\\
	+	Even though only the //J// = 5/2 – 3/2 fine structure component of the //N// = 2 – 1 rotational transition was observed the resolved <sup>14</sup>N hyperfine structure secures the detection.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 02, 2006
	+
	+
	+	----
	+

sio

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:56:55 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== SiO in Space =====
	+
	+	Silicon monoxide, SiO, is very widespread in space. It is generally viewed as an indicator of shocks. It was among the first molecules detected in space by means of radio astronomy.\\
	+	R. W. Wilson, A. A. Penzias, K. B. Jefferts, M. Kutner, and P. Thaddeus\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1971ApJ...167L..97W\|Discovery of Interstellar Silicon Monoxide]]\\
	+	//Astrophys. J.// 167, L97–L100 (1971).\\
	+	The //J// = 3 – 2 transition of SiO near 130.2 GHz was detected in emission with the 11 m Kitt Peak telescope toward Sgr B2(OH).\\
	+	D. F. Dickinson\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1972ApJ...175L..43D\|Detection of Silicon Monoxide at 87 GHz]]\\
	+	//Astrophys. J.// 175, L43–L100 (1972).\\
	+	The 11 m Kitt Peak telescope was used to detect the line toward Sgr B2(OH) and Orion A.
	+
	+	P. Schilke, G. Pineau des Forêts, C. M. Walmsley, and J. Martín-Pintado\\
	+	performed\\
	+	[[https://doi.org/10.1051/0004-6361:20010470\|Observations of SiO towards Photon Dominated Regions]]\\
	+	//Astron. Astrophys.// 372, 291–301 (2001).\\
	+	The IRAM 30 m telecope was used to detect several SiO transitions toward the Orion Bar and S 140.
	+
	+	S. Yamamoto, H. Mikami, S. Saito, N. Kaifu, M. Ohishi, and K. Kawaguchi\\
	+	detected\\
	+	[[https://ui.adsabs.harvard.edu/abs/1992PASJ...44..459Y\|SiO in Barnard 1]]\\
	+	//Publs. Astron. Soc. Japan// 167, L97–L100 (1971),\\
	+	a low-mass star-forming region.
	+
	+	The molecule is conspicuously absent in cold, quiescent molecular clouds, as reported by\\
	+	L. M. Ziurys, P. Friberg, and W. M. Irvine,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1989ApJ...343..201Z\|Interstellar SiO as a Tracer of High-temperature Chemistry]]\\
	+	//Astrophys. J.// 343, 201–207 (1989).\\
	+	The absence of SiO was reported for TMC-1, L134N (aka L183) and for B335 (aka L663). Hence,\\
	+	J. Martin-Pintado, R. Bachiller, and A. Fuente\\
	+	view\\
	+	[[https://ui.adsabs.harvard.edu/abs/1992A%26A...254..315M\|SiO Emission as a Tracer of Shocked Gas in Molecular Outflows]]\\
	+	//Astron. Astrophys.// 254, 315–326 (1992).
	+
	+	L. E. Snyder and D. Buhl\\
	+	proposed the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1974ApJ...189L..31S\|Detection of Possible Maser Emission Near 3.48 Millimeters from an Unidentified Molecular Species in Orion]]\\
	+	//Astrophys. J.// 189, L31–L33 (1974).\\
	+	Orion A was observed with the 11 m Kitt Peak telescope. The frequency coincidence with the //J// = 2 – 1 transition of SiO in its first excited vibrational state was noted.\\
	+	Confirmation came from\\
	+	J. H. Davis, G. N. Blair, H. van Till, and P. Thaddeus,\\
	+	who studied\\
	+	[[https://ui.adsabs.harvard.edu/abs/1974ApJ...189L..31S\|Vibrationally Excited Silicon Monoxide in the Orion Nebula]]\\
	+	//Astrophys. J.// 190, L117–L119 (1974).\\
	+	They observed the //J// = 3 – 2 transition of SiO.
	+
	+	D. Buhl, L. E. Snyder, F. J. Lovas, and D. R. Johnson\\
	+	reported subsequently on\\
	+	[[https://ui.adsabs.harvard.edu/abs/1974ApJ...192L..97B\|Silicon Monoxide: Detection of Maser Emission from the Second Vibrationally Excited State]]\\
	+	//Astrophys. J.// 192, L97–L100 (1974).\\
	+	Half of the authors are laboratory spectroscopists, thus highlighting the crucial importance for radio astronomical observations.
	+
	+	T. Kaminski, C. A. Gottlieb, K. H. Young, K. M. Menten, and N. A. Patel\\
	+	performed\\
	+	[[https://doi.org/10.1088/0067-0049/209/2/38\|An Interferometric Spectral Line and Imaging Survey of VY Canis Majoris in the 345 GHz Band]]\\
	+	//Astrophys. J. Suppl. Ser.// 209, Art. No. 38 (2013),\\
	+	and detected a //v// = 5 SiO maser.
	+
	+	E. Gonzalez-Alfonso, J. Alcolea, and J. Cernicharo\\
	+	reported on the\\
	+	[[https://ui.adsabs.harvard.edu/abs/1996A%26A...313L..13G\|Detection of <sup>29</sup>SiO //v// = 3 //J// = 8 → 7 Maser Emission: a new IR SiO Overlap]]\\
	+	//Astron. Astrophys.// 313, L13–L16 (1996).
	+
	+	S.-H. Cho, H.-G. Kim, Y.-S. Park, C.-H. Choi, and N. Ukita\\
	+	reported on the\\
	+	[[https://doi.org/10.1086/426585\|First Detection of <sup>28</sup>Si<sup>18</sup>O Maser and Thermal Emission from Orion KL]]\\
	+	//Astrophys. J.// 622, 390–392 (2005).
	+
	+	L. Decin, J. Cernicharo, M. J. Barlow, et al.\\
	+	investigated\\
	+	[[https://doi.org/10.1051/0004-6361/201014562\|Silicon in the Dust Formation Zone of IRC +10216]]\\
	+	//Astron. Astrophys.// 518, Art. No. L143 (2010).\\
	+	Using the PACS low-resolution spectrometer on board of the //Herschel// satellite, they identified unblended SiO rotational transitions beyond 3 THz.
	+
	+	The observation of <sup>28</sup>Si<sup>17</sup>O was reported by\\
	+	L. Velilla Prieto, C. Sánchez Contreras, J. Cernicharo, M. Agúndez, G. Quintana-Lacaci, V. Bujarrabal, J. Alcolea, C. Balança, F. Herpin, K. M. Menten, and F. Wyrowski\\
	+	in the course of\\
	+	[[https://doi.org/10.1051/0004-6361/201628776\|The Millimeter IRAM-30m Line Survey toward IK Tauri]]\\
	+	//Astron. Astrophys.// 597, Art. No. A25 (2017).
	+
	+	L. Decin, A. M. S. Richards, T. Danilovich, W. Homan, and J. A. Nuth\\
	+	reported on an\\
	+	[[https://doi.org/10.1051/0004-6361/201732216\|ALMA Spectral Line and Imaging Survey of a Low and a High Mass-loss Rate AGB Star between 335 and 362 GHz]]\\
	+	//Astron. Astrophys.// 615, Art. No. A28 (2018).\\
	+	The low mass-loss star was R Dor, the high mass-loss star was IK Tau. The very sensitive data permitted detection of <sup>29</sup>Si<sup>18</sup>O and <sup>30</sup>Si<sup>18</sup>O.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 12, 2014; 10, 2018
	+
	+
	+	----
	+

sip

anonymous@undisclosed.example.com (Anonymous) — Fri, 24 Nov 2023 12:33:22 +0000

2022/12/16 13:11		current
Line 3:		Line 3:
	L. A. Koelemay, M. A. Burton, A. P. Singh, P. M. Sheridan, J. J. Bernal, and L. M. Ziurys\\		L. A. Koelemay, M. A. Burton, A. P. Singh, P. M. Sheridan, J. J. Bernal, and L. M. Ziurys\\
	described the\\		described the\\
-	**[[https://doi.org/10.3847/2041-8213/ac9d9b\|Laboratory and Astronomical Detection of the SiP Radical (X<sup>2</sup>Π<sub>i</sub>): More Circumstellar	+	[[https://doi.org/10.3847/2041-8213/ac9d9b\|Laboratory and Astronomical Detection of the SiP Radical (X<sup>2</sup>Π<sub>i</sub>): More Circumstellar Phosphorus]]\\
-	Phosphorus]]**\\	+
	//Astrophys. J. Lett.// 940, Art. No. L11 (2022).\\		//Astrophys. J. Lett.// 940, Art. No. L11 (2022).\\
-	Dedicated observations of CW Leonis with the ARO 12 m dish at Kitt Peak as well as observations (dedicated and from a line survey) with the ARO SMT in the regions of the <sup>2</sup>Π<sub>3/2</sub>, //J"// = 7.5, 12.5, 15.5, and 16.5 transitions of SiP. Only the //J"// = 12.5 and 15.5 transitions near 215.05 and 262.81 GHz appear to be unblended. While this is fine for a tentative detection, it is too little for us to qualify for a definitive detection.	+	Dedicated observations of CW Leonis with the ARO 12 m dish at Kitt Peak as well as observations (dedicated and from a line survey) with the ARO SMT in the regions of the <sup>2</sup>Π<sub>3/2</sub>, //J"// = 7.5, 12.5, 15.5, and 16.5 transitions of SiP. Only the //J"// = 12.5 and 15.5 transitions near 215.05 and 262.81 GHz appear to be unblended. While this is fine for a tentative detection, it is too little for us to qualify for a definitive detection. The authors derive peak abundances only slightly lower than CP and even slightly higher than PN, but somewhat closer to the star.\\
		+	\\

	----		----

sis

anonymous@undisclosed.example.com (Anonymous) — Fri, 18 Oct 2019 10:58:41 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== SiS in Space =====
	+
	+	Silicon monosulfide, SiS, is a very abundant molecule in the inner regions of the circumstellar envelop of IRC+10216 (CW Leo) where it is thought to be the progenitor of much of the Si-chemistry. It was reported first by\\
	+	M. Morris, W. Gilmore, P. Palmer, B. E. Turner, and B. Zuckerman,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1975ApJ...199L..47M\|Detection of Interstellar SiS and a Study of the IRC +10216 Molecular Envelope]]\\
	+	//Astrophys. J.// 199, L47–L51 (1975).\\
	+	The 11 m Kitt Peak telescope was used to detect the //J// = 6 – 5 and 5 – 4 transitions near 108.9 and 90.8 GHz, respectively.
	+
	+	The first paper, mentioned in the previous paragraph, also reports on the tentative detection of SiS toward Sgr B2. In the meantime, there have been several reports on SiS in massive star-forming regions.\\
	+	D. F. Dickinson and E. N. Rodriguez Kuiper\\
	+	reported on\\
	+	[[https://ui.adsabs.harvard.edu/abs/1981ApJ...247..112D\|Interstellar silicon sulfide]]\\
	+	//Astrophys. J.// 247, 112–115 (1981).\\
	+	The same transitions as above were detected toward Sgr B2, and the 6 – 5 transition was detected toward Orion A.
	+
	+	L. Podio, C. Codella, B. Lefloch, N. Balucani, C. Ceccarelli, R. Bachiller, M. Benedettini, J. Cernicharo, N. Faginas-Lago, F. Fontani, A. Gusdorf, and M. Rosi\\
	+	reported on\\
	+	[[https://doi.org/10.1093/mnrasl/slx068\|Silicon-bearing Molecules in the Shock L1157-B1: First Detection of SiS around a Sun-like Protostar]]\\
	+	//MNRAS Lett.// 470, L16–L20 (2017).\\
	+	Six millimeter and submillimeter transitions of SiS were observed with the IRAM 30 m telescope.
	+
	+	A total of seven rare isotopic species has been detected since. These involve <sup>29</sup>SiS and Si<sup>34</sup>S:\\
	+	L. E. B. Johansson, C. Andersson, J. Ellder, P. Friberg, Å. Hjalmarson, B. Höglund, W. M. Irvine, H. Olofsson, and G. Rydbeck,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1984A%26A...130..227J\|Spectral Scan of Orion A and IRC+10216 from 72 to 91 GHz]]\\
	+	//Astron. Astrophys.// 130, 227–256 (1984);\\
	+	<sup>30</sup>SiS:\\
	+	L. M. Ziurys, D. P. Clemens, R. J. Saykally, M. Colvin, H. F. Schaefer,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1984ApJ...281..219Z\|A Search for Interstellar Silicon Nitride]]\\
	+	//Astrophys. J.// 281, 219–224 (1984);\\
	+	Si<sup>33</sup>S:\\
	+	C. Kahane, J. Gomez-Gonzalez, J. Cernicharo, and M. Guélin,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1988A%26A...190..167K\|Carbon, Nitrogen, Sulfur and Silicon Isotopic Ratios in the Envelope of IRC +10216]]\\
	+	//Astron. Astrophys.// 190, 167–177 (1988);\\
	+	<sup>29</sup>Si<sup>34</sup>S and <sup>30</sup>Si<sup>34</sup>S:\\
	+	J. Cernicharo, M. Guélin, and C. Kahane,\\
	+	[[https://ui.adsabs.harvard.edu/abs/2000A%26AS..142..181C\|A λ 2 mm Molecular Line Survey of the C-Star Envelope IRC +10216]]\\
	+	//Astron. Astrophys. Suppl.// 142, 181–215 (2000);\\
	+	and Si<sup>36</sup>S:\\
	+	R. Mauersberger, U. Ott, C. Henkel, J. Cernicharo, and R. Gallino,\\
	+	[[https://doi.org/10.1051/0004-6361:20040451\|The Abundance of <sup>36</sup>S in IRC +10216 and its Production in the Galaxy]]\\
	+	//Astron. Astrophys.// 426, 219–227 (2004).\\
	+
	+
	+	Maser activity in //v// = 0 of the main isotopic species has been reported first by\\
	+	C. Henkel, H. E. Matthews, and M. Morris,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1983ApJ...267..184H\|SiS Maser Emission from IRC +10216]]\\
	+	//Astrophys. J.// 267, 184–190 (1983).\\
	+	J. P. Fonfría Expósito, M. Agúndez, B. Tercero, J. R. Pardo, and J. Cernicharo\\
	+	reported on\\
	+	[[https://doi.org/10.1086/507104\|High-//J// //v// = 0 SiS Maser Emission in IRC +10216: A New Case of Infrared Overlaps]]\\
	+	//Astrophys. J.// 646, L127–L130 (2006).\\
	+	Transitions //J// = 11 – 10, 14 – 13, and 15 – 14 were found to be masing.
	+
	+	Vibrationally excited SiS has been detected by\\
	+	B. E. Turner,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...183L..23T\|Detection of Vibrationally Excited SiS in IRC +10216]]\\
	+	//Astron. Astrophys.// 183, L23–L26 (1987).\\
	+	L. Velilla Prieto, J. Cernicharo, G. Quintana-Lacaci, M. Agúndez, A. Castro-Carrizo, J. P. Fonfría, N. Marcelino, J. Zúñiga, A. Requena, and A. Bastida\\
	+	reported on\\
	+	[[https://doi.org/10.1088/2041-8205/805/2/L13\|Si-bearing Molecules Toward IRC+10216: ALMA Unveils the Molecular Envelope of CW Leo]]\\
	+	//Astrophys. J.// 805, Art. No. L13 (2015).\\
	+	In the case of the main isotopic species of SiS, transitions up to //v// = 7, possibly higher, were detected. In addition, emission lines of vibrationally excited minor isotopic species were reported.
	+
	+	Rovibrational transitions were observed by\\
	+	R. J. Boyle, J. J. Keady, D. E. Jennings, K. L. Hirsch, and G. R. Wiedemann,\\
	+	[[https://ui.adsabs.harvard.edu/abs/1994ApJ...420..863B\|Observations of 13.5 micron Rotation-Vibration Lines of SiS in IRC +10216]]\\
	+	//Astrophys. J.// 420, 863–868 (1994).
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller, 02, 2007; 06, 2008; 07, 2017; 12, 2017.
	+
	+	----
	+

so2

anonymous@undisclosed.example.com (Anonymous) — Mon, 25 Feb 2019 21:38:48 +0000

2026/04/11 23:41	current
Line 1:	Line 1:
	+	===== Detections of Sulfur Dioxide, SO2, in Space =====
	+
	+	L. E. Snyder, J. M. Hollis, B. L. Ulich, F. J. Lovas, D. R. Johnson, and D. Buhl\\
	+	reported on the\\
	+	[[http://cdsads.u-strasbg.fr/abs/1975ApJ...198L..81S\|Radio Detection of Interstellar Sulfur Dioxide]]\\
	+	//Astrophys. J.// 198, L81–L84 (1975).\\
	+	The NRAO 11 m dish was used to detect three transition in the Orion Molecular Cloud-1: 8<sub>1,7</sub> – 8<sub>0,8</sub> (83688.093 MHz); 8<sub>3,5</sub> – 9<sub>2,8</sub> (86639.088 MHz); and 7<sub>3,5</sub> – 8<sub>2,6</sub> (97702.334 MHz).
	+
	+	F. P. Schloerb, P. Friberg, Å. Hjalmarson, B. Höglund, and W. M. Irvine\\
	+	reported on\\
	+	[[http://cdsads.u-strasbg.fr/abs/1983ApJ...264..161S\|Observations of Sulfur Dioxide in the Kleinmann-Low Nebula]]\\
	+	//Astrophys. J.// 284, 161 – 171 (1983).\\
	+	The OSO 20 m dish was used to detect several transitions of SO<sub>2</sub> along with three of <sup>34</sup>SO<sub>2</sub>.
	+
	+	W. M. Irvine, J. C. Good, and F. P. Schloerb\\
	+	reported on\\
	+	[[http://cdsads.u-strasbg.fr/abs/1983A&A...127L..10I\|Observations of SO<sub>2</sub> and HCS<sup>+</sup> in Cold Molecular Clouds]]\\
	+	//Astron. Astrophys.// 127, L10 – L13 (1983).\\
	+	The FCRAO 14 m dish was used to detect the SO<sub>2</sub> 3<sub>1,3</sub> – 2<sub>0,2</sub> transition near 104029.42 MHz toward the L183 dark cloud.
	+
	+
	+	----
	+
	+	Contributor(s): H. S. P. Müller; 07, 2017
	+
	+
	+	----
	+

ti-oxide

anonymous@undisclosed.example.com (Anonymous) — Thu, 10 Dec 2020 10:38:20 +0000

2020/12/10 11:31		current
Line 40:		Line 40:
	[[https://doi.org/10.3847/1538-4357/abc079\|Rotational Spectra of Vibrationally Excited AlO and TiO in Oxygen-rich Stars]]\\		[[https://doi.org/10.3847/1538-4357/abc079\|Rotational Spectra of Vibrationally Excited AlO and TiO in Oxygen-rich Stars]]\\
	//Astrophys. J.// 904, Art. No. 110 (2020).\\		//Astrophys. J.// 904, Art. No. 110 (2020).\\
-	//J// = 11 → 10 transitions with Ω = 1, 2, and 3 were found in the circumstellar envelope of R Doradus up to //v// = 2 and that of IK Taure up to //v// = 1.\\	+	//J// = 11 → 10 transitions of TiO with Ω = 1, 2, and 3 were found in the circumstellar envelope of R Doradus up to //v// = 2 and that of IK Tauri up to //v// = 1.\\

	----		----
Line 62:		Line 62:
	----		----

-	Contributor(s): H. S. P. Müller; 03, 2013; 03, 2017	+	Contributor(s): H. S. P. Müller; 03, 2013; 03, 2017; 12, 2020

	----		----

vcn

anonymous@undisclosed.example.com (Anonymous) — Thu, 24 Oct 2019 07:25:16 +0000

vynh2

anonymous@undisclosed.example.com (Anonymous) — Tue, 08 Mar 2022 13:52:31 +0000

2021/12/06 14:04		current
Line 6:		Line 6:
	//Astrophys. J. Lett.// 920 (2021), Art. No. L27.\\		//Astrophys. J. Lett.// 920 (2021), Art. No. L27.\\
	Vinylamine (C<sub>2</sub>H<sub>3</sub>NH<sub>2</sub>) was detected through five un- or slightly blended transitions and four partially blended transitions with 4 ≤ //J// ≤ 9 and //K<sub>a</sub>// ≤ 3 in the course of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the IRAM 30 m dish at 3 mm. The lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> = 18 ± 3 K. Vinylamine is about a factor of 50 less abundant than methylamine.\\		Vinylamine (C<sub>2</sub>H<sub>3</sub>NH<sub>2</sub>) was detected through five un- or slightly blended transitions and four partially blended transitions with 4 ≤ //J// ≤ 9 and //K<sub>a</sub>// ≤ 3 in the course of an unbiased molecular line survey of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius B2(N), carried out with the IRAM 30 m dish at 3 mm. The lines were modeled quite well employing an LTE fit with //T//<sub>rot</sub> = 18 ± 3 K. Vinylamine is about a factor of 50 less abundant than methylamine.\\
-	Using additional observations with the Yebes 40 m dish at 7 mm, the authors identify tentatively four lines of ethylamine (C<sub>2</sub>H<sub>5</sub>NH<sub>2</sub>) with modest signal-to-noise ratio that appear to be not or only slightly blended and three that are somewhat more blended. The fit results suggest that ethylamine would be about a factor of 125 less abundant than methylamine.\\	+	Using additional observations with the Yebes 40 m dish at 7 mm, the authors identify tentatively four lines of ethylamine (C<sub>2</sub>H<sub>5</sub>NH<sub>2</sub>) with modest signal-to-noise ratio that appear to be not or only slightly blended and three that are somewhat more blended. The fit results suggest that ethylamine would be about a factor of 125 less abundant than methylamine. The identification appears to be very reasonable. Therefore, the molecule shows now up in the table as tentatively detected.\\

	----		----

-	Contributor(s): H. S. P. Müller; 12, 2021	+	Contributor(s): H. S. P. Müller; 12, 2021; 03, 2022

	----		----

vyoh

anonymous@undisclosed.example.com (Anonymous) — Thu, 04 Aug 2022 10:45:30 +0000

2022/08/04 11:37		current
Line 23:		Line 23:
	[[https://doi.org/10.1051/0004-6361/202142699\|Precursors of Fatty Alcohols in the ISM: Discovery of //n//-Propanol]]\\		[[https://doi.org/10.1051/0004-6361/202142699\|Precursors of Fatty Alcohols in the ISM: Discovery of //n//-Propanol]]\\
	//Astron. Astrophys.// 663 (2022), Art. No. A181.\\		//Astron. Astrophys.// 663 (2022), Art. No. A181.\\
		+	Using data from line surveys of the quiescent giant molecular cloud G+0.693−0.027, about 1' north-east of Sagittarius (Sgr) B2(N) carried out with the Yebes 40 m dish at 7 mm and with the IRAM 30 m dish at 3, 2, and 1 mm, the authors also identified //syn//- and //anti//-ethenol in a column density ratio of about 10 : 1. Interestingly, ethanol and ethanal are only about a factor of 5 and 4, respectively, more abundant than ethenol.\\
		+	\\

	----		----

2019/02/25 22:38		current
Line 2:		Line 2:

	F. Combes, M. Gerin, A. Wooten, G. Wlodarczak, F. Clausset, and P. J. Encrenaz,\\		F. Combes, M. Gerin, A. Wooten, G. Wlodarczak, F. Clausset, and P. J. Encrenaz,\\
-	[[http://cdsads.u-strasbg.fr/abs/1987A%26A...180L..13C\|Acetone in Interstellar Space]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...180L..13C\|Acetone in Interstellar Space]]\\
	//Astron. Astrophys.// 180, L13–L16 (1987);\\		//Astron. Astrophys.// 180, L13–L16 (1987);\\
	detected propanone, aka acetone, for the first time in the interstellar medium. Observations were made with the IRAM 30m, Greenbank 43m, and Kitt Peak 12m telescopes toward Sgr B2. The column density of 5 × 10<sup>13</sup> cm<sup>–2</sup> were much higher than values predicted by models of that time. Therefore, this detection was not accepted by many in the community for a long time.		detected propanone, aka acetone, for the first time in the interstellar medium. Observations were made with the IRAM 30m, Greenbank 43m, and Kitt Peak 12m telescopes toward Sgr B2. The column density of 5 × 10<sup>13</sup> cm<sup>–2</sup> were much higher than values predicted by models of that time. Therefore, this detection was not accepted by many in the community for a long time.
Line 8:		Line 8:
	15 years later, this detection was confirmed:\\		15 years later, this detection was confirmed:\\
	L. E. Snyder, F. J. Lovas, D. M. Mehringer, N. Y. Miao, Y.-J. Kuan, J. M. Hollis, and P. R. Jewell,\\		L. E. Snyder, F. J. Lovas, D. M. Mehringer, N. Y. Miao, Y.-J. Kuan, J. M. Hollis, and P. R. Jewell,\\
-	[[http://dx.doi.org/10.1086/342273\|Confirmation of Interstellar Acetone]]\\	+	[[https://doi.org/10.1086/342273\|Confirmation of Interstellar Acetone]]\\
	//Astrophys. J.// 578, 245–255 (2002).\\		//Astrophys. J.// 578, 245–255 (2002).\\

Line 14:		Line 14:
	More recently, propanone was detected towards the high-mass star-forming region Orion KL:\\		More recently, propanone was detected towards the high-mass star-forming region Orion KL:\\
	D. N. Friedel, L. E. Snyder, A. J. Remijan, and B. E. Turner,\\		D. N. Friedel, L. E. Snyder, A. J. Remijan, and B. E. Turner,\\
-	[[http://dx.doi.org/10.1086/497986\|Detection of Interstellar Acetone toward the Orion-KL Hot Core]]\\	+	[[https://doi.org/10.1086/497986\|Detection of Interstellar Acetone toward the Orion-KL Hot Core]]\\
	//Astrophys. J.// 632, L95–L98 (2005).\\		//Astrophys. J.// 632, L95–L98 (2005).\\
	Besides a very large number of transitions in its ground vibrational state, a few lines of the first excited torsional state were reported. Even though the number of vibrationally excited lines is small, the consistent global modeling ensures this aspect of the detection.		Besides a very large number of transitions in its ground vibrational state, a few lines of the first excited torsional state were reported. Even though the number of vibrationally excited lines is small, the consistent global modeling ensures this aspect of the detection.
Line 20:		Line 20:
	J. M. Lykke, A. Coutens, J. K. Jørgensen, M. H. D. van der Wiel, R. T. Garrod, H. S. P. Müller, P. Bjerkeli, T. L. Bourke, H. Calcutt, M. N. Drozdovskaya, C. Favre, E. C. Fayolle, S. K. Jacobsen, K. I. Öberg, M. V. Persson, E. F. van Dishoeck, and S. F. Wampfler\\		J. M. Lykke, A. Coutens, J. K. Jørgensen, M. H. D. van der Wiel, R. T. Garrod, H. S. P. Müller, P. Bjerkeli, T. L. Bourke, H. Calcutt, M. N. Drozdovskaya, C. Favre, E. C. Fayolle, S. K. Jacobsen, K. I. Öberg, M. V. Persson, E. F. van Dishoeck, and S. F. Wampfler\\
	reported on\\		reported on\\
-	[[http://dx.doi.org/10.1051/0004-6361/201629180\|The ALMA-PILS Survey: First Detections of Ethylene Oxide, Acetone and Propanal toward the Low-mass Protostar IRAS 16293–2422]]\\	+	[[https://doi.org/10.1051/0004-6361/201629180\|The ALMA-PILS Survey: First Detections of Ethylene Oxide, Acetone and Propanal toward the Low-mass Protostar IRAS 16293–2422]]\\
	//Astrophys. J.// 597, Art. No. A53 (2017).\\		//Astrophys. J.// 597, Art. No. A53 (2017).\\
	This report is the first one on the detection of acetone around a low-mass protostar. The Protostellar Interferometric Line Survey (PILS) was carried out with ALMA in its Band 7 (329 – 363 GHz). A total of 186 lines were assigned to acetone.		This report is the first one on the detection of acetone around a low-mass protostar. The Protostellar Interferometric Line Survey (PILS) was carried out with ALMA in its Band 7 (329 – 363 GHz). A total of 186 lines were assigned to acetone.
Line 28:		Line 28:

	Contributor(s): H. S. P. Müller; 02, 2006; 01, 2017		Contributor(s): H. S. P. Müller; 02, 2006; 01, 2017
-

	----		----

2019/02/25 22:38		current
Line 3:		Line 3:
	In 1985, several unidentified lines observed toward several sources, were assigned to the aromatic molecule cyclopropenylidene by\\		In 1985, several unidentified lines observed toward several sources, were assigned to the aromatic molecule cyclopropenylidene by\\
	P. Thaddeus, J. M. Vrtilek, and C. A. Gottlieb,\\		P. Thaddeus, J. M. Vrtilek, and C. A. Gottlieb,\\
-	[[http://cdsads.u-strasbg.fr/abs/1985ApJ...299L..63T\|Laboratory and Astronomical Identification of Cyclopropenylidene, C<sub>3</sub>H<sub>2</sub>]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1985ApJ...299L..63T\|Laboratory and Astronomical Identification of Cyclopropenylidene, C<sub>3</sub>H<sub>2</sub>]],\\
	//Astrophys. J.// 299, L63–L66 (1985).		//Astrophys. J.// 299, L63–L66 (1985).

	The first observation of an initially unidentified line concerned one of the //ortho// ground state lines 2<sub>12</sub> – 1<sub>01</sub> in emission at 82093.54 GHz toward the diverse molecular clouds Ori A, Sgr B2(OH), and TMC-1 by\\		The first observation of an initially unidentified line concerned one of the //ortho// ground state lines 2<sub>12</sub> – 1<sub>01</sub> in emission at 82093.54 GHz toward the diverse molecular clouds Ori A, Sgr B2(OH), and TMC-1 by\\
	P. Thaddeus, M. Guélin, and R. A. Linke,\\		P. Thaddeus, M. Guélin, and R. A. Linke,\\
-	[[http://cdsads.u-strasbg.fr/abs/1981ApJ...246L..41T\|Three New 'Nonterrestrial' Molecules]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1981ApJ...246L..41T\|Three New 'Nonterrestrial' Molecules]],\\
	//Astrophys. J.// 246, L41–L45 (1981).		//Astrophys. J.// 246, L41–L45 (1981).

	An interesting aspect has been found by\\		An interesting aspect has been found by\\
	H. E. Matthews, S. C. Madden, L. W. Avery, and W. M. Irvine,\\		H. E. Matthews, S. C. Madden, L. W. Avery, and W. M. Irvine,\\
-	[[http://cdsads.u-strasbg.fr/abs/1986ApJ...307L..69M\|The C<sub>3</sub>H<sub>2</sub> 2<sub>20</sub> – 2<sub>11</sub> Transition: Absorption in Cold Dark Clouds]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1986ApJ...307L..69M\|The C<sub>3</sub>H<sub>2</sub> 2<sub>20</sub> – 2<sub>11</sub> Transition: Absorption in Cold Dark Clouds]],\\
	//Astrophys. J.// 307, L69–L73 (1986).		//Astrophys. J.// 307, L69–L73 (1986).

	Observations of the two <sup>13</sup>C isotopomers of cyclopropenylidene were reported first by J. Gómez-González, M. Guélin, J. Cernicharo, C. Kahane, and M. Bogey,\\		Observations of the two <sup>13</sup>C isotopomers of cyclopropenylidene were reported first by J. Gómez-González, M. Guélin, J. Cernicharo, C. Kahane, and M. Bogey,\\
-	[[http://cdsads.u-strasbg.fr/abs/1986A%26A...168L..11G\|Detection of Interstellar <sup>13</sup>C Isotopes of C<sub>3</sub>H<sub>2</sub>]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1986A%26A...168L..11G\|Detection of Interstellar <sup>13</sup>C Isotopes of C<sub>3</sub>H<sub>2</sub>]],\\
	//Astron. Astrophys.// 168, L11–L12 (1986).\\		//Astron. Astrophys.// 168, L11–L12 (1986).\\
	They observed the 2<sub>12</sub> – 1<sub>01</sub> transitions toward Sgr B2(OH).		They observed the 2<sub>12</sub> – 1<sub>01</sub> transitions toward Sgr B2(OH).

	M. B. Bell, P. A. Feldman, H. E. Matthews, and L. W. Avery reported on the\\		M. B. Bell, P. A. Feldman, H. E. Matthews, and L. W. Avery reported on the\\
-	[[http://cdsads.u-strasbg.fr/abs/1986ApJ...311L..89B\|Detection of Deuterated Cyclopropenylidene (C<sub>3</sub>HD) in TMC-1]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1986ApJ...311L..89B\|Detection of Deuterated Cyclopropenylidene (C<sub>3</sub>HD) in TMC-1]],\\
	//Astrophys. J.// 311, L89–L92 (1986).\\		//Astrophys. J.// 311, L89–L92 (1986).\\
	The detection of multiply substituted isotopologs is currently hampered by the lack of published laboratory data.		The detection of multiply substituted isotopologs is currently hampered by the lack of published laboratory data.
Line 29:		Line 29:
	S. Spezzano, S. Brünken, P. Schilke, P. Caselli, K. M. Menten, M. C. McCarthy, L. Bizzocchi, S. P. Treviño-Morales, Y. Aikawa, and S. Schlemmer\\		S. Spezzano, S. Brünken, P. Schilke, P. Caselli, K. M. Menten, M. C. McCarthy, L. Bizzocchi, S. P. Treviño-Morales, Y. Aikawa, and S. Schlemmer\\
	reported on the\\		reported on the\\
-	[[http://dx.doi.org/10.1088/2041-8205/769/2/L19\|Interstellar Detection of //c//-C<sub>3</sub>D<sub>2</sub>]],\\	+	[[https://doi.org/10.1088/2041-8205/769/2/L19\|Interstellar Detection of //c//-C<sub>3</sub>D<sub>2</sub>]],\\
	//Astrophys. J.// 769, Art. No. L19 (2013)\\		//Astrophys. J.// 769, Art. No. L19 (2013)\\
	in the dark clouds TMC-1C and L1544 using the IRAM 30 m radio telescope. Three transitions were detected in the 3 mm wavelength region.		in the dark clouds TMC-1C and L1544 using the IRAM 30 m radio telescope. Three transitions were detected in the 3 mm wavelength region.
		+
		+	M. Agúndez, N. Marcelino, J. Cernicharo, E. Roueff, and M. Tafalla\\
		+	reported on\\
		+	**[[https://doi.org/10.1051/0004-6361/201935164\|A Sensitive //λ// 3 mm Line Survey of L483
		+	A Broad View of the Chemical Composition of a Core around a Class 0 object]]**,\\
		+	//Astron. Astrophys.// 625, Art. No. A147 (2019)\\
		+	Among the many species observed is cyclopropenylidene with one D and one <sup>13</sup>C.

	Cyclopropenylidene was also detected in the circumstellar envelope of the carbon-rich AGB star CW Leo by\\		Cyclopropenylidene was also detected in the circumstellar envelope of the carbon-rich AGB star CW Leo by\\
	K. Kawaguchi, Y. Kasai, S.-I. Ishikawa, N. Kaifu,\\		K. Kawaguchi, Y. Kasai, S.-I. Ishikawa, N. Kaifu,\\
-	[[http://cdsads.u-strasbg.fr/abs/1995PASJ...47..853K\|A Spectral-Line Survey Observation of IRC +10216 between 28 and 50 GHz]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1995PASJ...47..853K\|A Spectral-Line Survey Observation of IRC +10216 between 28 and 50 GHz]],\\
	//Publ. Astron. Soc. Japan// 47, 853–876 (1995).		//Publ. Astron. Soc. Japan// 47, 853–876 (1995).

	The molecule was also detected in the circumstellar envelope of a carbon-rich post-AGB star by\\		The molecule was also detected in the circumstellar envelope of a carbon-rich post-AGB star by\\
	P. Cox, R. Güsten, and C. Henkel,\\		P. Cox, R. Güsten, and C. Henkel,\\
-	[[http://cdsads.u-strasbg.fr/abs/1987A%26A...181L..19C\|Detection of the Hydrocarbon Ring Molecule C<sub>3</sub>H<sub>2</sub> in the Planetary Nebula NGC 7027]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...181L..19C\|Detection of the Hydrocarbon Ring Molecule C<sub>3</sub>H<sub>2</sub> in the Planetary Nebula NGC 7027]],\\
	//Astron. Astrophys.// 181, L19–L22 (1987).		//Astron. Astrophys.// 181, L19–L22 (1987).

	P. Cox, R. Güsten, and C. Henkel reported on the\\		P. Cox, R. Güsten, and C. Henkel reported on the\\
-	[[http://cdsads.u-strasbg.fr/abs/1988A%26A...206..108C\|Observations of C<sub>3</sub>H<sub>2</sub> in the Diffuse Interstellar Medium]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1988A%26A...206..108C\|Observations of C<sub>3</sub>H<sub>2</sub> in the Diffuse Interstellar Medium]],\\
	//Astron. Astrophys.// 206, 108–116 (1988).		//Astron. Astrophys.// 206, 108–116 (1988).

Line 50:		Line 57:
	----		----

-	Contributor(s): H. S. P. Müller; 03, 2011; 05, 2013	+	Contributor(s): H. S. P. Müller; 03, 2011; 05, 2013; 07,2019

	----		----

2021/12/20 12:47		current
Line 32:		Line 32:
	J. Cernicharo, M. Guélin, H. Hein, and C. Kahane,\\		J. Cernicharo, M. Guélin, H. Hein, and C. Kahane,\\
	[[https://ui.adsabs.harvard.edu/abs/1987A%26A...181L...9C\|Sulfur in IRC +10216]]\\		[[https://ui.adsabs.harvard.edu/abs/1987A%26A...181L...9C\|Sulfur in IRC +10216]]\\
-	//Astron. Astrophys.// 181, L9–L12 (1987).	+	//Astron. Astrophys.// 181, L9–L12 (1987).\\
		+	\\

	C<sub>2</sub>S was also seen toward several translucent clouds, albeit in only the lower energy transition of two by\\		C<sub>2</sub>S was also seen toward several translucent clouds, albeit in only the lower energy transition of two by\\
Line 38:		Line 39:
	**[[https://doi.org/10.1086/313077\|The Physics and Chemistry of Small Translucent Molecular Clouds.\\		**[[https://doi.org/10.1086/313077\|The Physics and Chemistry of Small Translucent Molecular Clouds.\\
	IX. Acetylenic Chemistry]]**\\		IX. Acetylenic Chemistry]]**\\
-	//Astrophys. J. Suppl. Ser.// 115, 91–118 (1998).	+	//Astrophys. J. Suppl. Ser.// 115, 91–118 (1998).\\
		+	\\

	The two <sup>13</sup>C isotopomers were detected with the Nobeyama 45 m telescope toward TMC-1 by\\		The two <sup>13</sup>C isotopomers were detected with the Nobeyama 45 m telescope toward TMC-1 by\\
Line 76:		Line 78:
	//Astron. Astrophys.// 570, Art. No. A45 (2014).\\		//Astron. Astrophys.// 570, Art. No. A45 (2014).\\
	The //J// + 1 → //J// transitions with //J// = 43, 44, and 45 of C<sub>5</sub>S were identified in the course of a 3 mm line survey with the IRAM 30 m telescope near 81.2, 83.0, and 84.9 GHz. The first transition is blended. The almost similar column densities between two carbon chain molecules, here C<sub>5</sub>S and C<sub>3</sub>S, are very unusual, though not unprecedented.\\		The //J// + 1 → //J// transitions with //J// = 43, 44, and 45 of C<sub>5</sub>S were identified in the course of a 3 mm line survey with the IRAM 30 m telescope near 81.2, 83.0, and 84.9 GHz. The first transition is blended. The almost similar column densities between two carbon chain molecules, here C<sub>5</sub>S and C<sub>3</sub>S, are very unusual, though not unprecedented.\\
		+	\\

	M. B. Bell, L. W. Avery, and P. A. Feldman\\		M. B. Bell, L. W. Avery, and P. A. Feldman\\
Line 82:		Line 85:
	//Astrophys. J.// 417, L37–L40 (1993).\\		//Astrophys. J.// 417, L37–L40 (1993).\\
	A line observed with the NRAO 43 m telecope near 24.0 GHz in the course of a molecular line survey was assigned to the //J// = 13 – 12 transition of C<sub>5</sub>S. The authors state in the abstract: "Assuming the observed feature is due to C<sub>5</sub>S, we find that //N//(C<sub>5</sub>S)///N//(C<sub>3</sub>S) ≈ 0.5." Confirmation of this finding or identification of further transitions at shorter wavelengths will be useful.\\		A line observed with the NRAO 43 m telecope near 24.0 GHz in the course of a molecular line survey was assigned to the //J// = 13 – 12 transition of C<sub>5</sub>S. The authors state in the abstract: "Assuming the observed feature is due to C<sub>5</sub>S, we find that //N//(C<sub>5</sub>S)///N//(C<sub>3</sub>S) ≈ 0.5." Confirmation of this finding or identification of further transitions at shorter wavelengths will be useful.\\
		+	\\

	The molecule was recently also identified in TMC-1 by\\		The molecule was recently also identified in TMC-1 by\\

2019/02/25 22:38		current
Line 3:		Line 3:
	The linear propynylidynium, C<sub>3</sub>H<sup>+</sup>, was detected with the IRAM 30 m telescope in nine transitions (//J//" = 3 to 11) in the course of a molecular line survey of the Horsehead Nebula in Orion, covering the 3, 2, and 1.3 mm regions, by\\		The linear propynylidynium, C<sub>3</sub>H<sup>+</sup>, was detected with the IRAM 30 m telescope in nine transitions (//J//" = 3 to 11) in the course of a molecular line survey of the Horsehead Nebula in Orion, covering the 3, 2, and 1.3 mm regions, by\\
	J. Pety, P. Gratier, V. Guzmán, E. Roueff, M. Gerin, J. R. Goicoechea, S. Bardeau, A. Sievers, F. Le Petit, J. Le Bourlot, A. Belloche, and D. Talbi,\\		J. Pety, P. Gratier, V. Guzmán, E. Roueff, M. Gerin, J. R. Goicoechea, S. Bardeau, A. Sievers, F. Le Petit, J. Le Bourlot, A. Belloche, and D. Talbi,\\
-	[[http://dx.doi.org/10.1051/0004-6361/201220062\|The IRAM-30 m Line Survey of the Horsehead PDR. II. First detection of the //l//-C<sub>3</sub>H<sup>+</sup> Hydrocarbon Cation]],\\	+	[[https://doi.org/10.1051/0004-6361/201220062\|The IRAM-30 m Line Survey of the Horsehead PDR. II. First detection of the //l//-C<sub>3</sub>H<sup>+</sup> Hydrocarbon Cation]],\\
	//Astron. Astrophys.// 548, Art. No. A68 (2012).\\		//Astron. Astrophys.// 548, Art. No. A68 (2012).\\
-	In the absence of laboratory data, the identification was secured through quantum chemical calculations.	+	In the absence of laboratory data, the identification was secured through quantum chemical calculations.\\

	R. C. Fortenberry, X. Huang, T. D. Crawford, and T. J. Lee,\\		R. C. Fortenberry, X. Huang, T. D. Crawford, and T. J. Lee,\\
	however, proposed\\		however, proposed\\
-	[[http://dx.doi.org/10.1088/2041-8205/768/2/L25\|High-accuracy Quartic Force Field Calculations for the Spectroscopic Constants and Vibrational Frequencies of 1 <sup>1</sup>//A'// //l//-C<sub>3</sub>H<sup>–</sup>: A Possible Link to Lines Observed in the Horsehead Nebula Photodissociation Region]],\\	+	[[https://doi.org/10.1088/2041-8205/768/2/L25\|High-accuracy Quartic Force Field Calculations for the Spectroscopic Constants and Vibrational Frequencies of 1 <sup>1</sup>//A'// //l//-C<sub>3</sub>H<sup>–</sup>: A Possible Link to Lines Observed in the Horsehead Nebula Photodissociation Region]],\\
	//Astrophys. J.// 772, Art. No. 39 (2013).\\		//Astrophys. J.// 772, Art. No. 39 (2013).\\
-	In an earlier publication, some of the authors found a discrepancy between their calculated equilibrium quartic distortion parameter and the ground state quartic distortion parameter derived from astronomical observations. As a results, they proposed to reject //l//-C<sub>3</sub>H<sup>+</sup> as carrier of the emission features mentioned above. Instead, they now propose the anion in its excited singlet state as the carrier of the emission lines.	+	In an earlier publication, some of the authors found a discrepancy between their calculated equilibrium quartic distortion parameter and the ground state quartic distortion parameter derived from astronomical observations. As a results, they proposed to reject //l//-C<sub>3</sub>H<sup>+</sup> as carrier of the emission features mentioned above. Instead, they now propose the anion in its excited singlet state as the carrier of the emission lines.\\

	Considering that the Horsehead PDR may well be far from LTE conditions, one should not reject the idea of the anion as carrier entirely. But the occurance of anions in a PDR as well as other regions (see below) in general or of C<sub>3</sub>H<sup>–</sup> in particular needs to be verified.\\		Considering that the Horsehead PDR may well be far from LTE conditions, one should not reject the idea of the anion as carrier entirely. But the occurance of anions in a PDR as well as other regions (see below) in general or of C<sub>3</sub>H<sup>–</sup> in particular needs to be verified.\\
	Moreover, the rejection of the assignment to the cation based on the deviations in the calculated equilibrium versus observed ground state distortion parameters is not compelling as vibrational averaging in other molecules has created much larger deviations.\\		Moreover, the rejection of the assignment to the cation based on the deviations in the calculated equilibrium versus observed ground state distortion parameters is not compelling as vibrational averaging in other molecules has created much larger deviations.\\
-	Finally, laboratory experiments carried out at the CfA by K. Crabtree and M. C. McCarthy favor the cation as carrier of these lines.	+	Finally, laboratory experiments carried out at the CfA by K. Crabtree and M. C. McCarthy favor the cation as carrier of these lines.\\

	B. A. McGuire, P. B. Carroll, R. A. Loomis, G. A. Blake, J. M. Hollis, F. J. Lovas, P. R. Jewell, A. J. Remijan\\		B. A. McGuire, P. B. Carroll, R. A. Loomis, G. A. Blake, J. M. Hollis, F. J. Lovas, P. R. Jewell, A. J. Remijan\\
	reported on\\		reported on\\
-	[[http://dx.doi.org/10.1088/0004-637X/774/1/56\|A Search for //l//-C<sub>3</sub>H<sup>+</sup> and //l//-C<sub>3</sub>H in Sgr B2(N), Sgr B2(OH), and the Dark Cloud TMC-1]],\\	+	[[https://doi.org/10.1088/0004-637X/774/1/56\|A Search for //l//-C<sub>3</sub>H<sup>+</sup> and //l//-C<sub>3</sub>H in Sgr B2(N), Sgr B2(OH), and the Dark Cloud TMC-1]],\\
	//Astrophys. J.// 774, Art. No. 56 (2013).\\		//Astrophys. J.// 774, Art. No. 56 (2013).\\
-	The //J"// = 0 and 1 transitions of //l//-C<sub>3</sub>H<sup>+</sup> (or an alterantive carrier) were abserved in absorption in their line survey of Sgr B2(N) carried aout with the GBT 100 m telescope. A suitable, albeit blended emission at the //J"// = 6 transition was found in archival survey data. Archival survey data toward Sgr B2(OH) and TMC-1 were not unambiguous, but would yield //l//-C<sub>3</sub>H column density ratios similar to those found for the Horsehead PDR and for Sgr B2(N). These findings make it more interesting and important to establish or reject by laboratory spectroscopy that the carrier of these lines is //l//-C<sub>3</sub>H<sup>+</sup> or to present an alternative carrier.	+	The //J"// = 0 and 1 transitions of //l//-C<sub>3</sub>H<sup>+</sup> (or an alterantive carrier) were abserved in absorption in their line survey of Sgr B2(N) carried out with the GBT 100 m telescope. A suitable, albeit blended emission at the //J"// = 6 transition was found in archival survey data. Archival survey data toward Sgr B2(OH) and TMC-1 were not unambiguous, but would yield //l//-C<sub>3</sub>H column density ratios similar to those found for the Horsehead PDR and for Sgr B2(N). These findings make it more interesting and important to establish or reject by laboratory spectroscopy that the carrier of these lines is //l//-C<sub>3</sub>H<sup>+</sup> or to present an alternative carrier.\\

	S. Brünken, L. Kluge, A. Stoffels, O. Asvany, and S. Schlemmer\\		S. Brünken, L. Kluge, A. Stoffels, O. Asvany, and S. Schlemmer\\
	reported on the\\		reported on the\\
-	[[http://dx.doi.org/10.1088/2041-8205/783/1/L4\|Laboratory Rotational Spectrum of //l//-C<sub>3</sub>H<sup>+</sup> and Confirmation of its Astronomical Detection]],\\	+	[[https://doi.org/10.1088/2041-8205/783/1/L4\|Laboratory Rotational Spectrum of //l//-C<sub>3</sub>H<sup>+</sup> and Confirmation of its Astronomical Detection]],\\
	//Astrophys. J.// 783, Art. No. L4 (2014).\\		//Astrophys. J.// 783, Art. No. L4 (2014).\\
-	A novel, charge-selective form of action spectroscopy was employed to measure accurately the //J"// = 1 to 4 transition frequencies.	+	A novel, charge-selective form of action spectroscopy was employed to measure accurately the //J"// = 1 to 4 transition frequencies.\\

		+	J. Cernicharo, M. Agúndez, C. Cabezas, R. Fuentetaja, B. Tercero, N. Marcelino, Y. Endo, J. R. Pardo, and P. de Vicente\\
		+	reported on the\\
		+	[[https://doi.org/10.1051/0004-6361/202142992\|Discovery of C<sub>5</sub>H<sup>+</sup> and Detection of C<sub>3</sub>H<sup>+</sup> in TMC-1 with the QUIJOTE Line Survey]],\\
		+	//Astron. Astrophys.// 657, Art. No. L16 (2022).\\
		+	C<sub>5</sub>H<sup>+</sup> was found to be a factor of 3.7 ± 0.5 more abundant than C<sub>3</sub>H<sup>+</sup>, which was explained by the reactivity of the latter with H<sub>2</sub> through chemical modeling. The authors refuted the earlier identification of C<sub>3</sub>H<sup>+</sup> in archival TMC-1 data by McGuire et al. in 2013.\\

	----		----

-	Contributor(s): H. S. P. Müller; 11, 2012; 05, 2013; 07, 2013; 02, 2014	+	Contributor(s): H. S. P. Müller; 11, 2012; 05, 2013; 07, 2013; 02, 2014; 03, 2022

	----		----
-

2019/02/25 22:38		current
Line 1:		Line 1:
	===== On Searches for 1,3-Dihydroxypropanone and 1,2-Dihydroxypropanal in the ISM =====		===== On Searches for 1,3-Dihydroxypropanone and 1,2-Dihydroxypropanal in the ISM =====

-	The first report on the detection of [[./glycolaldehyd.html\|hydroxyethanal]], CH<sub>2</sub>OHCHO, aka glycolaldehyde, in the interstellar medium was met with great enthusiasm as this molecule represents a more complex precursor to sugars than the ubiquitous methanal, H<sub>2</sub>CO, aka formaldehyde. Very recently, there has been a report on the detection of 1,3-dihydroxypropanone in Sgr B2(N-LMH):\\	+	The first report on the detection of [[molecules:ism:glycolaldehyd\|hydroxyethanal]], CH<sub>2</sub>OHCHO, aka glycolaldehyde, in the interstellar medium was met with great enthusiasm as this molecule represents a more complex precursor to sugars than the ubiquitous methanal, H<sub>2</sub>CO, aka formaldehyde. Very recently, there has been a report on the detection of 1,3-dihydroxypropanone in Sgr B2(N-LMH):\\
	S. L. Widicus Weaver and G. A. Blake,\\		S. L. Widicus Weaver and G. A. Blake,\\
-	[[http://dx.doi.org/10.1086/430407\|1,3-Dihydroxyacetone in Sagittarius B2(N-LMH): The First Interstellar Ketose]]\\	+	[[https://doi.org/10.1086/430407\|1,3-Dihydroxyacetone in Sagittarius B2(N-LMH): The First Interstellar Ketose]]\\
	//Astrophys. J.// 624, L33–L36 (2005);\\		//Astrophys. J.// 624, L33–L36 (2005);\\
-	[[http://dx.doi.org/10.1086/497963\|Erratum]]\\	+	[[https://doi.org/10.1086/497963\|Erratum]]\\
	//Astrophys. J.// 632, L163 (2005).\\		//Astrophys. J.// 632, L163 (2005).\\
	A column density was derived that was very high: about a factor of three higher than that of H<sub>2</sub>CO – that seems rather peculiar.		A column density was derived that was very high: about a factor of three higher than that of H<sub>2</sub>CO – that seems rather peculiar.
Line 11:		Line 11:
	One more recent paper seriously questions the findings mentioned above:\\		One more recent paper seriously questions the findings mentioned above:\\
	A. J. Apponi, D. T. Halfen, L. M. Ziurys, J. M. Hollis, A. Remijan, and F. J. Lovas,\\		A. J. Apponi, D. T. Halfen, L. M. Ziurys, J. M. Hollis, A. Remijan, and F. J. Lovas,\\
-	[[http://dx.doi.org/10.1086/504979\|Investigating the Limits of Chemical Complexity in Sagittarius B2(N): A Rigorous Attempt to Confirm 1,3-Dihydroxyacetone]]\\	+	[[https://doi.org/10.1086/504979\|Investigating the Limits of Chemical Complexity in Sagittarius B2(N): A Rigorous Attempt to Confirm 1,3-Dihydroxyacetone]]\\
	//Astrophys. J.// 643, L29–L32 (2006).\\		//Astrophys. J.// 643, L29–L32 (2006).\\
	No line was identified unambiguously. The upper limit derived for 1,3-dihydroxypropanone was lower than the column density derived above by a factor of about 300 and about a factor of four below that of hydroxyethanal. Moreover, it was pointed out that the column density of 1,3-dihydroxypropanone may be lower still by about a factor of six or so if the column density ratio 1,3-dihydroxypropanone : hydroxyethanal corresponds to that of hydroxyethanal : methanal. Even though this does not have to be correct this assumption is certainly reasonable.		No line was identified unambiguously. The upper limit derived for 1,3-dihydroxypropanone was lower than the column density derived above by a factor of about 300 and about a factor of four below that of hydroxyethanal. Moreover, it was pointed out that the column density of 1,3-dihydroxypropanone may be lower still by about a factor of six or so if the column density ratio 1,3-dihydroxypropanone : hydroxyethanal corresponds to that of hydroxyethanal : methanal. Even though this does not have to be correct this assumption is certainly reasonable.
Line 19:		Line 19:
	1,2-Dihydroxypropanal, aka glyceraldehyde, is an isomer of 1,3-dihydroxypropanone. It has been searched for unsuccessfully by:\\		1,2-Dihydroxypropanal, aka glyceraldehyde, is an isomer of 1,3-dihydroxypropanone. It has been searched for unsuccessfully by:\\
	J. M. Hollis, P. R. Jewell, F. J. Lovas, A. Remijan, and H. Møllendal,\\		J. M. Hollis, P. R. Jewell, F. J. Lovas, A. Remijan, and H. Møllendal,\\
-	[[http://dx.doi.org/10.1086/423200\|Green Bank Telescope Detection of New Interstellar Aldehydes: Propenal and Propanal]]\\	+	[[https://doi.org/10.1086/423200\|Green Bank Telescope Detection of New Interstellar Aldehydes: Propenal and Propanal]]\\
	//Astrophys. J.// 610, L21–L24 (2004).\\		//Astrophys. J.// 610, L21–L24 (2004).\\
	The upper limit for 1,2-dihydroxypropanal is similar to that of 1,3-dihydroxypropanone in the paper above.		The upper limit for 1,2-dihydroxypropanal is similar to that of 1,3-dihydroxypropanone in the paper above.
Line 27:		Line 27:

	Contributor(s): H. S. P. Müller; 05, 2006		Contributor(s): H. S. P. Müller; 05, 2006
-

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2019/02/25 22:38		current
Line 3:		Line 3:
	The hexatriynyl radical in its <sup>2</sup>Π<sub>3/2</sub> lower spin component has been detected toward TMC-1 by\\		The hexatriynyl radical in its <sup>2</sup>Π<sub>3/2</sub> lower spin component has been detected toward TMC-1 by\\
	H. Suzuki, M. Ohishi, N. Kaifu, S.-I. Ishikawa, and T. Kasuga,\\		H. Suzuki, M. Ohishi, N. Kaifu, S.-I. Ishikawa, and T. Kasuga,\\
-	[[http://cdsads.u-strasbg.fr/abs/1986PASJ...38..911S\|Detection of the Interstellar C<sub>6</sub>H Radical]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1986PASJ...38..911S\|Detection of the Interstellar C<sub>6</sub>H Radical]],\\
	//Publ. Astron. Soc. Japan// 38 911–917 (1986) and\\		//Publ. Astron. Soc. Japan// 38 911–917 (1986) and\\
-	[[http://cdsads.u-strasbg.fr/abs/1987PASJ...39..193S\|Detection of C<sub>6</sub>H in the <sup>2</sup>Π<sub>1/2</sub> State toward IRC +10216]] by\\	+	[[https://ui.adsabs.harvard.edu/abs/1987PASJ...39..193S\|Detection of C<sub>6</sub>H in the <sup>2</sup>Π<sub>1/2</sub> State toward IRC +10216]] by\\
	S. Saito, K. Kawaguchi, H. Suzuki, M. Ohishi, N. Kaifu, and S.-I. Ishikawa,\\		S. Saito, K. Kawaguchi, H. Suzuki, M. Ohishi, N. Kaifu, and S.-I. Ishikawa,\\
	//Publ. Astron. Soc. Japan// 39 193–199 (1987)\\		//Publ. Astron. Soc. Japan// 39 193–199 (1987)\\
Line 12:		Line 12:
	Transitions of the lowest excited //v//<sub>11</sub> = 1 vibrational state have been identified very recently:\\		Transitions of the lowest excited //v//<sub>11</sub> = 1 vibrational state have been identified very recently:\\
	J. Cernicharo, M. Guélin, M. Agúndez, M. C. McCarthy, and P. Thaddeus,\\		J. Cernicharo, M. Guélin, M. Agúndez, M. C. McCarthy, and P. Thaddeus,\\
-	[[http://dx.doi.org/10.1086/595583\|Detection of C<sub>5</sub>N<sup>–</sup> and Vibrationally Excited C<sub>6</sub>H in IRC +10216]]\\	+	[[https://doi.org/10.1086/595583\|Detection of C<sub>5</sub>N<sup>–</sup> and Vibrationally Excited C<sub>6</sub>H in IRC +10216]]\\
	//Astrophys. J.// 688 L83–L86 (2008).\\		//Astrophys. J.// 688 L83–L86 (2008).\\
	The Renner-Teller interaction causes this state to split into three components: <sup>2</sup>Σ<sup>–</sup>, <sup>2</sup>Δ with spin-orbit splitting, and <sup>2</sup>Σ<sup>+</sup>. The lowest <sup>2</sup>Σ<sup>–</sup> state as well as both spin-components of the <sup>2</sup>Δ state were detected. The <sup>2</sup>Σ<sup>+</sup> was not seen; it is probably overlapped by the lower <sup>2</sup>Σ<sup>–</sup> state and possibly too weak to be recognized.		The Renner-Teller interaction causes this state to split into three components: <sup>2</sup>Σ<sup>–</sup>, <sup>2</sup>Δ with spin-orbit splitting, and <sup>2</sup>Σ<sup>+</sup>. The lowest <sup>2</sup>Σ<sup>–</sup> state as well as both spin-components of the <sup>2</sup>Δ state were detected. The <sup>2</sup>Σ<sup>+</sup> was not seen; it is probably overlapped by the lower <sup>2</sup>Σ<sup>–</sup> state and possibly too weak to be recognized.
Line 20:		Line 20:

	Contributor(s): H. S. P. Müller; 11, 2006; 10, 2008		Contributor(s): H. S. P. Müller; 11, 2006; 10, 2008
-

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2019/04/25 13:35		current
Line 3:		Line 3:
	Ethyl cyanide, C<sub>2</sub>H<sub>5</sub>CN, aka propanenitrile, is a fairly prototypical hot core molecule. It was detected first toward OMC-1 and Sgr B2:\\		Ethyl cyanide, C<sub>2</sub>H<sub>5</sub>CN, aka propanenitrile, is a fairly prototypical hot core molecule. It was detected first toward OMC-1 and Sgr B2:\\
	D. R. Johnson, F. J. Lovas, C. A. Gottlieb, E. W. Gottlieb, M. M. Litvak, P. Thaddeus, and M. Guélin,\\		D. R. Johnson, F. J. Lovas, C. A. Gottlieb, E. W. Gottlieb, M. M. Litvak, P. Thaddeus, and M. Guélin,\\
-	[[http://cdsads.u-strasbg.fr/abs/1977ApJ...218..370J\|Detection of Interstellar Ethyl Cyanide]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1977ApJ...218..370J\|Detection of Interstellar Ethyl Cyanide]]\\
-	//Astrophys. J.// 218, L370–L376 (1977).	+	//Astrophys. J.// 218, L370–L376 (1977).\\

	More recently, however, it has also been detected toward a low-mass star-forming region:\\		More recently, however, it has also been detected toward a low-mass star-forming region:\\
Line 19:		Line 19:
	D. M. Mehringer, J. C. Pearson, J. Keene, and T. G. Philips,\\		D. M. Mehringer, J. C. Pearson, J. Keene, and T. G. Philips,\\
	[[https://doi.org/10.1086/386357\|Detection of Vibrationally Excited Ethyl Cyanide in the Interstellar Medium]]\\		[[https://doi.org/10.1086/386357\|Detection of Vibrationally Excited Ethyl Cyanide in the Interstellar Medium]]\\
-	//Astrophys. J.// 608, 306–313 (2004).	+	//Astrophys. J.// 608, 306–313 (2004).\\

	These states as well as higher vibrational states up to v<sub>12</sub> = 1 at 770 K were detected toward Orion KL by\\		These states as well as higher vibrational states up to v<sub>12</sub> = 1 at 770 K were detected toward Orion KL by\\
Line 28:		Line 28:
	A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\		A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\
	[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\		[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\
-	//Astron. Astrophys.// 559, Art. No. A47 (2013).	+	//Astron. Astrophys.// 559, Art. No. A47 (2013).\\

	The three <sup>13</sup>C isotopic species have been reported first in observations toward Orion IRc2 by\\		The three <sup>13</sup>C isotopic species have been reported first in observations toward Orion IRc2 by\\
Line 38:		Line 38:
	H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, and P. Schilke,\\		H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, and P. Schilke,\\
	[[https://doi.org/10.1016/j.jms.2008.03.016\|Rotational Spectroscopy of Isotopic Vinyl Cyanide, H<sub>2</sub>C=CH–C≡N, in the Laboratory and in Space]],\\		[[https://doi.org/10.1016/j.jms.2008.03.016\|Rotational Spectroscopy of Isotopic Vinyl Cyanide, H<sub>2</sub>C=CH–C≡N, in the Laboratory and in Space]],\\
-	//J. Mol. Spectrosc.// 250, 319–325 (2008).	+	//J. Mol. Spectrosc.// 250, 319–325 (2008).\\

	The detection of the <sup>15</sup>N isotopolog (in Orion KL) was reported first by\\		The detection of the <sup>15</sup>N isotopolog (in Orion KL) was reported first by\\
	L. Margulès, R. Motiyenko, K. Demyk, B. Tercero, J. Cernicharo, M. Sheng, M. Weidmann, J. Gripp, H. Mäder, and J. Demaison,\\		L. Margulès, R. Motiyenko, K. Demyk, B. Tercero, J. Cernicharo, M. Sheng, M. Weidmann, J. Gripp, H. Mäder, and J. Demaison,\\
	[[https://doi.org/10.1051/0004-6361:200810889\|Rotational Spectrum of Deuterated and <sup>15</sup>N Ethyl Cyanides: CH<sub>3</sub>CHDCN and CH<sub>2</sub>DCH<sub>2</sub>CN and of CH<sub>3</sub>CH<sub>2</sub>C<sup>15</sup>N]]\\		[[https://doi.org/10.1051/0004-6361:200810889\|Rotational Spectrum of Deuterated and <sup>15</sup>N Ethyl Cyanides: CH<sub>3</sub>CHDCN and CH<sub>2</sub>DCH<sub>2</sub>CN and of CH<sub>3</sub>CH<sub>2</sub>C<sup>15</sup>N]]\\
-	//Astron. Astrophys.// **559, Art. No. A47 (2013**).\\	+	//Astron. Astrophys.// **493, 565 (2009**).\\
	The isotopolog was also detected in Sagittarius B2(N2), the northern, secondary hot-core of Sgr B2(N), by\\		The isotopolog was also detected in Sagittarius B2(N2), the northern, secondary hot-core of Sgr B2(N), by\\
	A. Belloche, H. S. P. Müller, R. T. Garrod, and K. M. Menten,\\		A. Belloche, H. S. P. Müller, R. T. Garrod, and K. M. Menten,\\
Line 65:		Line 65:

	Contributor(s): H. S. P. Müller; 07, 2004; 03/04 2007; 10, 2010; 06, 2016		Contributor(s): H. S. P. Müller; 07, 2004; 03/04 2007; 10, 2010; 06, 2016
-

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2019/02/25 22:38		current
Line 1:		Line 1:
	===== The Detection of Ethanimine in the ISM =====		===== The Detection of Ethanimine in the ISM =====

-	Ethanimine, CH<sub>3</sub>CHNH, is the the next heavier homolog of [[http://www.astro.uni-koeln.de/site/vorhersagen/molecules/ism/H2CNH.html\|methanimine]], H<sub>2</sub>CNH. It has been identified in spectra taken with the GBT 100 m telescope toward Sgr B2(N) by\\	+	Ethanimine, CH<sub>3</sub>CHNH, is the the next heavier homolog of [[molecules:ism:H2CNH\|methanimine]], H<sub>2</sub>CNH. It has been identified in spectra taken with the GBT 100 m telescope toward Sgr B2(N) by\\
	R. A. Loomis, D. P. Zaleski, A. L. Steber, J. L. Neill, M. T. Muckle, B. J. Harris, J. M. Hollis, P. R. Jewell, V. Lattanzi, F. J. Lovas, O. Martinez, Jr., M. C. McCarthy, A. J. Remijan, B. H. Pate, and J. F. Corby,\\		R. A. Loomis, D. P. Zaleski, A. L. Steber, J. L. Neill, M. T. Muckle, B. J. Harris, J. M. Hollis, P. R. Jewell, V. Lattanzi, F. J. Lovas, O. Martinez, Jr., M. C. McCarthy, A. J. Remijan, B. H. Pate, and J. F. Corby,\\
-	[[http://dx.doi.org/10.1088/2041-8205/765/1/L9\|The Detection of Interstellar Ethanimine (CH<sub>3</sub>CHNH) from Observations Taken during the GBT PRIMOS Survey]]\\	+	[[https://doi.org/10.1088/2041-8205/765/1/L9\|The Detection of Interstellar Ethanimine (CH<sub>3</sub>CHNH) from Observations Taken during the GBT PRIMOS Survey]]\\
	//Astrophys. J// 765, Art. No. 9 (2013).\\		//Astrophys. J// 765, Art. No. 9 (2013).\\
	6 rotational transitions were detected for the lower energy //E//-conformer and 4 for the higher energy //Z//-conformer. The transitions had //J// < 4 and //K<sub>a</sub>// < 1, occured between 13 and 48 GHz and were mostly seen in absorption. Two higher energy rotational transitions of the //E//-conformer were seen in emission. All transitions displayed well resolved CH<sub>3</sub> internal rotation splitting and some showed <sup>14</sup>N hyperfine splitting. The lines were detected in the two well known velocity components 64 km/s and 82 km/s, though (partial) overlap occured for the latter in some lines. A rotational temperature of 6 K was assumed.\\		6 rotational transitions were detected for the lower energy //E//-conformer and 4 for the higher energy //Z//-conformer. The transitions had //J// < 4 and //K<sub>a</sub>// < 1, occured between 13 and 48 GHz and were mostly seen in absorption. Two higher energy rotational transitions of the //E//-conformer were seen in emission. All transitions displayed well resolved CH<sub>3</sub> internal rotation splitting and some showed <sup>14</sup>N hyperfine splitting. The lines were detected in the two well known velocity components 64 km/s and 82 km/s, though (partial) overlap occured for the latter in some lines. A rotational temperature of 6 K was assumed.\\
	These, as well as other observations of fairly complex molecules toward Sgr B2(N) at apperently low rotational temperatures, may be related to findings by\\		These, as well as other observations of fairly complex molecules toward Sgr B2(N) at apperently low rotational temperatures, may be related to findings by\\
	M. A. Requena-Torres, J. Martín-Pintado, A. Rodríguez-Franco, S. Martín, N. J. Rodríguez-Fernández, and P. de Vicente,\\		M. A. Requena-Torres, J. Martín-Pintado, A. Rodríguez-Franco, S. Martín, N. J. Rodríguez-Fernández, and P. de Vicente,\\
-	[[http://dx.doi.org/10.1051/0004-6361:20065190\|Organic Molecules in the Galactic Center – Hot Core Chemistry without Hot Cores]]\\	+	[[https://doi.org/10.1051/0004-6361:20065190\|Organic Molecules in the Galactic Center – Hot Core Chemistry without Hot Cores]]\\
	//Astron. Astrophys.// 455, 971–985 (2006);\\		//Astron. Astrophys.// 455, 971–985 (2006);\\
	and by\\		and by\\
	M. A. Requena-Torres, J. Martín-Pintado, S. Martín, and M. R. Morris,\\		M. A. Requena-Torres, J. Martín-Pintado, S. Martín, and M. R. Morris,\\
-	[[http://dx.doi.org/10.1086/523627\|The Galactic Center: The Largest Oxygen-bearing Organic Molecule Repository]]\\	+	[[https://doi.org/10.1086/523627\|The Galactic Center: The Largest Oxygen-bearing Organic Molecule Repository]]\\
	//Astrophys. J.// 672, 352–360 (2008).		//Astrophys. J.// 672, 352–360 (2008).

Line 19:		Line 19:

	Contributor(s): H. S. P. Müller; 02, 2013		Contributor(s): H. S. P. Müller; 02, 2013
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2019/02/27 12:26		current
Line 5:		Line 5:
	Ethanol in its lowest //anti// configuration was among the early molecules to be detected in space. Its first detection was reported by:\\		Ethanol in its lowest //anti// configuration was among the early molecules to be detected in space. Its first detection was reported by:\\
	B. Zuckerman, B. E. Turner, D. R. Johnson, F. O. Clark, F. J. Lovas, N. Fourikis, P. Palmer, M. Morris, A. E. Lilley, J. A. Ball, C. A. Gottlieb, and H. Penfield,\\		B. Zuckerman, B. E. Turner, D. R. Johnson, F. O. Clark, F. J. Lovas, N. Fourikis, P. Palmer, M. Morris, A. E. Lilley, J. A. Ball, C. A. Gottlieb, and H. Penfield,\\
-	[[http://cdsads.u-strasbg.fr/abs/1975ApJ...196L..99Z\|Detection of Interstellar //trans//-Ethyl Alcohol]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1975ApJ...196L..99Z\|Detection of Interstellar //trans//-Ethyl Alcohol]]\\
	//Astrophys. J.// 196, L99–L102 (1975).\\		//Astrophys. J.// 196, L99–L102 (1975).\\
	Three //b//-type transitions (6<sub>06</sub> – 5<sub>15</sub>, 4<sub>14</sub> – 3<sub>03</sub>, and 5<sub>15</sub> – 4<sub>04</sub>) were detected with the 36-foot NRAO telescope in the 3 mm region toward the massive star-forming region Sagittarius B2(OH). Since then, //anti//-ethanol was detected in many massive star-forming regions, including W51M, G34.3+0.15, and Orion KL as well as other molecular clouds with somewhat elevated temperatures (around 100 K).		Three //b//-type transitions (6<sub>06</sub> – 5<sub>15</sub>, 4<sub>14</sub> – 3<sub>03</sub>, and 5<sub>15</sub> – 4<sub>04</sub>) were detected with the 36-foot NRAO telescope in the 3 mm region toward the massive star-forming region Sagittarius B2(OH). Since then, //anti//-ethanol was detected in many massive star-forming regions, including W51M, G34.3+0.15, and Orion KL as well as other molecular clouds with somewhat elevated temperatures (around 100 K).
Line 11:		Line 11:
	The molecule was also detected in some of the investigated Galactic center molecular clouds which have low dust temperatures (10–20 K), even lower rotational temperatures (around 10 K), which are moderately dense (a few tenthousand molecules per cubic centimeter), but which are kinetically moderately warm (about 100 K or more). Two or three transitions were detected with the IRAM 30 m telescope in the 3 mm range by\\		The molecule was also detected in some of the investigated Galactic center molecular clouds which have low dust temperatures (10–20 K), even lower rotational temperatures (around 10 K), which are moderately dense (a few tenthousand molecules per cubic centimeter), but which are kinetically moderately warm (about 100 K or more). Two or three transitions were detected with the IRAM 30 m telescope in the 3 mm range by\\
	M. A. Requena-Torres, J. Martín-Pintado, A. Rodríguez-Franco, S. Martín, N. J. Rodríguez-Fernández, and P. de Vicente,\\		M. A. Requena-Torres, J. Martín-Pintado, A. Rodríguez-Franco, S. Martín, N. J. Rodríguez-Fernández, and P. de Vicente,\\
-	[[http://dx.doi.org/10.1051/0004-6361:20065190\|Organic Molecules in the Galactic Center – Hot Core Chemistry without Hot Cores]]\\	+	[[https://doi.org/10.1051/0004-6361:20065190\|Organic Molecules in the Galactic Center – Hot Core Chemistry without Hot Cores]]\\
	//Astron. Astrophys.// 455, 971–985 (2006).		//Astron. Astrophys.// 455, 971–985 (2006).

	S. E. Bisschop, J. K. Jørgensen, T. L. Bourke, S. Bottinelli, and E. F. van Dishoeck,\\		S. E. Bisschop, J. K. Jørgensen, T. L. Bourke, S. Bottinelli, and E. F. van Dishoeck,\\
	used the SMA to carry out\\		used the SMA to carry out\\
-	[[http://dx.doi.org/10.1051/0004-6361:200809673\|An interferometric study of the low-mass protostar IRAS 16293-2422: small scale organic chemistry]]\\	+	[[https://doi.org/10.1051/0004-6361:200809673\|An interferometric study of the low-mass protostar IRAS 16293-2422: small scale organic chemistry]]\\
	//Astron. Astrophys.// 488, 959–968 (2008).\\		//Astron. Astrophys.// 488, 959–968 (2008).\\
	They found evidence for the presence of ethanol in this low mass protostellar object.		They found evidence for the presence of ethanol in this low mass protostellar object.
Line 22:		Line 22:
	J. C. Pearson, K. V. L. N. Sastry, E. Herbst, and F. C. De Lucia,\\		J. C. Pearson, K. V. L. N. Sastry, E. Herbst, and F. C. De Lucia,\\
	reported on the identification of 13 U-lines in Orion-KL as belonging to the higher lying //gauche//-conformer:\\		reported on the identification of 13 U-lines in Orion-KL as belonging to the higher lying //gauche//-conformer:\\
-	[[http://dx.doi.org/10.1086/303967\|//gauche// Ethyl Alcohol: Laboratory Assignments and Interstellar Identification]]\\	+	[[https://doi.org/10.1086/303967\|//gauche// Ethyl Alcohol: Laboratory Assignments and Interstellar Identification]]\\
	//Astrophys. J.// 480, 420–L102 (1997).\\		//Astrophys. J.// 480, 420–L102 (1997).\\
	All these lines are //c//-type //Q//-branch transitions with //K<sub>a</sub>// = 1 ↔ 0 and //J// between 17 and 31; they occur between 97.5 and 98.0 GHz. Only one line appeared to be blended with a line different from //gauche//-ethanol. Additional U-lines in the 3 mm region were also assigned to this conformer.		All these lines are //c//-type //Q//-branch transitions with //K<sub>a</sub>// = 1 ↔ 0 and //J// between 17 and 31; they occur between 97.5 and 98.0 GHz. Only one line appeared to be blended with a line different from //gauche//-ethanol. Additional U-lines in the 3 mm region were also assigned to this conformer.
Line 28:		Line 28:
	H. S. P. Müller, A. Belloche, L.-H. Xu, R. M. Lees, R. T. Garrod, A. Walters, J. van Wijngaarden, F. Lewen, S. Schlemmer, and K. M. Menten,\\		H. S. P. Müller, A. Belloche, L.-H. Xu, R. M. Lees, R. T. Garrod, A. Walters, J. van Wijngaarden, F. Lewen, S. Schlemmer, and K. M. Menten,\\
	reported on\\		reported on\\
-	[[http://dx.doi.org/10.1051/0004-6361/201527470\|Exploring molecular complexity with ALMA (EMoCA): Alkanethiols and alkanols in Sagittarius B2(N2)]]\\	+	[[https://doi.org/10.1051/0004-6361/201527470\|Exploring molecular complexity with ALMA (EMoCA): Alkanethiols and alkanols in Sagittarius B2(N2)]]\\
	//Astron. Astrophys.// 587, Art. No. A92 (2016).\\		//Astron. Astrophys.// 587, Art. No. A92 (2016).\\
	A line survey of Sgr B2(N) was carried out with ALMA at 3 mm. Both <sup>13</sup>C isotopomers were detected with a <sup>12</sup>C/<sup>13</sup>C ratio of 25, which is usual in the Galactic Center.		A line survey of Sgr B2(N) was carried out with ALMA at 3 mm. Both <sup>13</sup>C isotopomers were detected with a <sup>12</sup>C/<sup>13</sup>C ratio of 25, which is usual in the Galactic Center.
Line 34:		Line 34:
	J. K. Jørgensen, H. S. P. Müller, H. Calcutt, A. Coutens, M. N. Drozdovskaya, K. I. Öberg, M. V. Persson, V. Taquet, E. F. van Dishoeck, and S. F. Wampfler\\		J. K. Jørgensen, H. S. P. Müller, H. Calcutt, A. Coutens, M. N. Drozdovskaya, K. I. Öberg, M. V. Persson, V. Taquet, E. F. van Dishoeck, and S. F. Wampfler\\
	reported on\\		reported on\\
-	[[http://dx.doi.org/10.1051/0004-6361/201731667\|The ALMA-PILS Survey: Isotopic Composition of Oxygen-containing Complex Organic Molecules toward IRAS 16293–2422B]]\\	+	[[https://doi.org/10.1051/0004-6361/201731667\|The ALMA-PILS Survey: Isotopic Composition of Oxygen-containing Complex Organic Molecules toward IRAS 16293–2422B]]\\
	//Astron. Astrophys.// 620, Art. No. A170 (2018).\\		//Astron. Astrophys.// 620, Art. No. A170 (2018).\\
	The results were obtained in the course of a line survey of the solar-type protostellar binary IRAS 16293–2422 with ALMA covering the frequency range 329.1–362.9 GHz. The authors only investigated source B. They detected for the first time the mono-deuterated isotopomers (three different ones; in addition, CH<sub>2</sub>DCH<sub>2</sub>OH has two conformers). The D/H ratio per H atom is about 0.05 to about 0.06. Lines of the two <sup>13</sup>C isotopomers were also detected, albeit not enough for a clear detection. The <sup>12</sup>C/<sup>13</sup>C ratio appears to be about 25, much lower than the local ISM value of 68. A confirmation of this value is desirable. Ethanol is among the molecules with warmer rotational temperatures of around 300 K in that hot corino.		The results were obtained in the course of a line survey of the solar-type protostellar binary IRAS 16293–2422 with ALMA covering the frequency range 329.1–362.9 GHz. The authors only investigated source B. They detected for the first time the mono-deuterated isotopomers (three different ones; in addition, CH<sub>2</sub>DCH<sub>2</sub>OH has two conformers). The D/H ratio per H atom is about 0.05 to about 0.06. Lines of the two <sup>13</sup>C isotopomers were also detected, albeit not enough for a clear detection. The <sup>12</sup>C/<sup>13</sup>C ratio appears to be about 25, much lower than the local ISM value of 68. A confirmation of this value is desirable. Ethanol is among the molecules with warmer rotational temperatures of around 300 K in that hot corino.
Line 42:		Line 42:

	Contributor(s): H. S. P. Müller; 11, 2009; 07, 2012; 11, 2016; 01, 2019		Contributor(s): H. S. P. Müller; 11, 2009; 07, 2012; 11, 2016; 01, 2019
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2019/05/09 12:38		current
Line 3:		Line 3:
	Formamide, HC(O)NH<sub>2</sub>, is a fairly typical hot core molecule that is quite abundant. The first transition of this molecule was detected toward Sgr B2 and likely toward Sgr A by\\		Formamide, HC(O)NH<sub>2</sub>, is a fairly typical hot core molecule that is quite abundant. The first transition of this molecule was detected toward Sgr B2 and likely toward Sgr A by\\
	R. H. Rubin, G. W. Swenson, Jr., R. C. Solomon, and H. L. Flygare,\\		R. H. Rubin, G. W. Swenson, Jr., R. C. Solomon, and H. L. Flygare,\\
-	[[http://cdsads.u-strasbg.fr/abs/1971ApJ...169L..39R\|Microwave Detection of Interstellar Formamide]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1971ApJ...169L..39R\|Microwave Detection of Interstellar Formamide]]\\
	//Astrophys. J.// 169, L39–L43 (1971).\\		//Astrophys. J.// 169, L39–L43 (1971).\\
	They detected all three Δ//F// = 0 hyperfine components of the //K<sub>a</sub>// = 1, //J// = 2 – 2 transition near 4619 MHz. Only the strongest component, overlapped in part with the H112α transition, was tentatively detected toward Sgr A.\\		They detected all three Δ//F// = 0 hyperfine components of the //K<sub>a</sub>// = 1, //J// = 2 – 2 transition near 4619 MHz. Only the strongest component, overlapped in part with the H112α transition, was tentatively detected toward Sgr A.\\
	The detection of a second, related, 1 – 1 transition toward Sgr B2 and Sgr A was reported by\\		The detection of a second, related, 1 – 1 transition toward Sgr B2 and Sgr A was reported by\\
	C. A. Gottlieb, P. Palmer, L. J. Richard, and B. Zuckerman\\		C. A. Gottlieb, P. Palmer, L. J. Richard, and B. Zuckerman\\
-	[[http://cdsads.u-strasbg.fr/abs/1973ApJ...182..699G\|Studies of Interstellar Formamide]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1973ApJ...182..699G\|Studies of Interstellar Formamide]]\\
	//Astrophys. J.// 182, 699–710 (1973).		//Astrophys. J.// 182, 699–710 (1973).

Line 22:		Line 22:
	//Astron. Astrophys.// 590, Art. No. L6 (2016).\\		//Astron. Astrophys.// 590, Art. No. L6 (2016).\\
	Carrying out a line survey toward IRAS 16293-2422 between 329 and 363 GHz, a deuteration degree of about two percent was derived for source B and for all three isotopomers assuming a <sup>12</sup>C/<sup>13</sup>C ratio of 68 because lines of the main isotopolog are frequently affected by optical depth effects.		Carrying out a line survey toward IRAS 16293-2422 between 329 and 363 GHz, a deuteration degree of about two percent was derived for source B and for all three isotopomers assuming a <sup>12</sup>C/<sup>13</sup>C ratio of 68 because lines of the main isotopolog are frequently affected by optical depth effects.
		+
		+	A. Belloche, R. T. Garrod, H. S. P. Müller, K. M. Menten, I. Medvedev, J. Thomas, and Z. Kisiel\\
		+	reported on\\
		+	[[https://doi.org/10.1051/0004-6361/201935428\|Re-exploring Molecular Complexity with ALMA (ReMoCA): Interstellar Detection of Urea]]\\
		+	//Astron. Astrophys.// 628, Art. No. A10 (2019).\\
		+	In the course of a new unbiased line survey toward the high-mass star-forming region Sagittarius (Sgr) B2(N) close to the Galactic center, HC(<sup>18</sup>O)NH<sub>2</sub> and HC(O)<sup>15</sup>NH<sub>2</sub> were detected. The <sup>16</sup>O/<sup>18</sup>O ratio of 140 is in the range of values found in the Galactic center, the <sup>14</sup>N/<sup>15</sup>N ratio is about 300.

	The molecule was also detected in several other hot core sources, such as Orion KL, G327.3–0.6, G34_3+0.15, and NGC 6334(I).		The molecule was also detected in several other hot core sources, such as Orion KL, G327.3–0.6, G34_3+0.15, and NGC 6334(I).
Line 52:		Line 58:

	Contributor(s): H. S. P. Müller; 05, 2009; 08, 2012; 02, 2013; 06, 2016; 10, 2017; 01, 2019		Contributor(s): H. S. P. Müller; 05, 2009; 08, 2012; 02, 2013; 06, 2016; 10, 2017; 01, 2019
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2019/04/26 15:39		current
Line 9:		Line 9:
	//Astrophys. J.// 554, L81–L85 (2001).\\		//Astrophys. J.// 554, L81–L85 (2001).\\
	6 //b//-type rotational transitions in the 70 to 105 GHz region were searched for with the NRAO 12 m radio telescope in the former work. Two transitions were severely blended, the remaining four appeared to be free of contamination. No rotational temeperature was derived, but 200 K were assumed. Because of the small number of lines and possible line overlap this detection had to be viewed with some caution until further observations.\\		6 //b//-type rotational transitions in the 70 to 105 GHz region were searched for with the NRAO 12 m radio telescope in the former work. Two transitions were severely blended, the remaining four appeared to be free of contamination. No rotational temeperature was derived, but 200 K were assumed. Because of the small number of lines and possible line overlap this detection had to be viewed with some caution until further observations.\\
-	The 8<sub>08</sub> – 7<sub>17</sub> transition near 82.471 GHz was studied with the BIMA array in the latter work. The molecule was found to be distributed over a large area of more than 60" with no pronounced peak at the Large Molecule Heimat hot core, in contrast to its isomers acetic acid and methyl formate, which are concentrated on a much smaller scale of less than 5". This indicates a much lower rotational temperature than the 200 K assumed earlier.	+	The 8<sub>08</sub> – 7<sub>17</sub> transition near 82.471 GHz was studied with the BIMA array in the latter work. The molecule was found to be distributed over a large area of more than 60" with no pronounced peak at the Large Molecule Heimat hot core, in contrast to its isomers acetic acid and methyl formate, which are concentrated on a much smaller scale of less than 5". This indicates a much lower rotational temperature than the 200 K assumed earlier.\\

	A report on interstellar glycolaldehyde had been presented at the 58th International Symposium on Molecular Spectroscopy; Columbus, OH, June 16–20, 2003:\\		A report on interstellar glycolaldehyde had been presented at the 58th International Symposium on Molecular Spectroscopy; Columbus, OH, June 16–20, 2003:\\
	D. T. Halfen, A. J. Apponi, and L. M. Ziurys,\\		D. T. Halfen, A. J. Apponi, and L. M. Ziurys,\\
	[[http://molspect.chemistry.ohio-state.edu/symposium_58/symposium/Abstracts/p181.pdf\|Glycolaldehyde Revisited: Can Large Organic Molecules be Accurately Identified in the Interstellar Medium ?]].\\		[[http://molspect.chemistry.ohio-state.edu/symposium_58/symposium/Abstracts/p181.pdf\|Glycolaldehyde Revisited: Can Large Organic Molecules be Accurately Identified in the Interstellar Medium ?]].\\
-	This contribution appeared to question the detection.	+	This contribution appeared to question the detection.\\

	Recent observations of the four lowest //<sup>r</sup>Q//<sub>0</sub> transitions in the microwave region toward Sgr B2(N) secure the glycolaldehyde detection:\\		Recent observations of the four lowest //<sup>r</sup>Q//<sub>0</sub> transitions in the microwave region toward Sgr B2(N) secure the glycolaldehyde detection:\\
Line 20:		Line 20:
	[[https://doi.org/10.1086/424927\|Green Bank Telescope Observations of Interstellar Glycolaldehyde: Low-Temperature Sugar]]\\		[[https://doi.org/10.1086/424927\|Green Bank Telescope Observations of Interstellar Glycolaldehyde: Low-Temperature Sugar]]\\
	//Astrophys. J.// 613, L45–L48 (2004).\\		//Astrophys. J.// 613, L45–L48 (2004).\\
-	Interestingly, these transitions point at temperatures of around 8 K, whereas a reanalysis of the millimeter wave transitions, observed by the same group and mentioned above, were reinterpreted in terms of a temperature of about 50 K.	+	Interestingly, these transitions point at temperatures of around 8 K, whereas a reanalysis of the millimeter wave transitions, observed by the same group and mentioned above, were reinterpreted in terms of a temperature of about 50 K.\\

	The observations from the Ziurys group have appeared eventually:\\		The observations from the Ziurys group have appeared eventually:\\
Line 29:		Line 29:
	Even though the article mentioned above already has secured the glycolaldehyde detection, this work is still worth mentioning because it shows how difficult it is to obtain definitive results for a moderately complex molecule. 40 (!) transitions have been searched for in the upper 4 mm region to the 2 mm region (68–169 GHz). No significant signals were detected for only two transitions which are fairly high in //K<sub>a</sub>//. Only 8 of the remaining 38 transitions appeared to be unaffected by features of other species. All others were overlapped to a varying amount. A sizeable number of features remained unassigned (U-lines). Thus, this work does not only emphasize the importance of searching for a sufficiently large number of spectral features of a desired moderately large molecule in order to prove its presence in certain media in space, but it also indicates the importance of knowing the identity of the U-lines in order to identify further molecules in space.\\		Even though the article mentioned above already has secured the glycolaldehyde detection, this work is still worth mentioning because it shows how difficult it is to obtain definitive results for a moderately complex molecule. 40 (!) transitions have been searched for in the upper 4 mm region to the 2 mm region (68–169 GHz). No significant signals were detected for only two transitions which are fairly high in //K<sub>a</sub>//. Only 8 of the remaining 38 transitions appeared to be unaffected by features of other species. All others were overlapped to a varying amount. A sizeable number of features remained unassigned (U-lines). Thus, this work does not only emphasize the importance of searching for a sufficiently large number of spectral features of a desired moderately large molecule in order to prove its presence in certain media in space, but it also indicates the importance of knowing the identity of the U-lines in order to identify further molecules in space.\\
	The rotational temperature derived from "clean" lines only is about 25 K; inclusion of some slightly blended lines yields a value of roughly 35 K.\\		The rotational temperature derived from "clean" lines only is about 25 K; inclusion of some slightly blended lines yields a value of roughly 35 K.\\
-	Some of the observed U-lines may be caused by presently not identified species. However, a considerable number of these U-lines are caused most definitively by known species in higher rotationally or vibrationally excited states or by minor isotopic species. It is also obvious that the unambiguous identification of molecules more complex than glycolaldehyde will be even more challenging.	+	Some of the observed U-lines may be caused by presently not identified species. However, a considerable number of these U-lines are caused most definitively by known species in higher rotationally or vibrationally excited states or by minor isotopic species. It is also obvious that the unambiguous identification of molecules more complex than glycolaldehyde will be even more challenging.\\

	The molecule was also detected in three Galactic center molecular clouds which have low dust temperatures (10–20 K), even lower rotational temperatures (around 10 K), which are moderately dense (a few tenthousand molecules per cubic centimeter), but which are kinetically moderately warm (about 100 K or more). Three or four transitions were detected with the 100 m GBT telescope between 13 and 23 GHz by\\		The molecule was also detected in three Galactic center molecular clouds which have low dust temperatures (10–20 K), even lower rotational temperatures (around 10 K), which are moderately dense (a few tenthousand molecules per cubic centimeter), but which are kinetically moderately warm (about 100 K or more). Three or four transitions were detected with the 100 m GBT telescope between 13 and 23 GHz by\\
	M. A. Requena-Torres, J. Martín-Pintado, S. Martín, and M. R. Morris,\\		M. A. Requena-Torres, J. Martín-Pintado, S. Martín, and M. R. Morris,\\
	[[https://doi.org/10.1086/523627\|The Galactic Center: The Largest Oxygen-bearing Organic Molecule Repository]]\\		[[https://doi.org/10.1086/523627\|The Galactic Center: The Largest Oxygen-bearing Organic Molecule Repository]]\\
-	//Astrophys. J.// 672, 352–360 (2008).	+	//Astrophys. J.// 672, 352–360 (2008).\\

	A report on the\\		A report on the\\
Line 40:		Line 40:
	by M. T. Beltrán, C. Codella, S. Viti, R. Neri, and R. Cesaroni,\\		by M. T. Beltrán, C. Codella, S. Viti, R. Neri, and R. Cesaroni,\\
	//Astrophys. J.// 690, L93–L96 (2009),\\		//Astrophys. J.// 690, L93–L96 (2009),\\
-	with the IRAM Plateau de Bure Interferometer toward the high mass star-forming region G31.41+0.31 should be viewed with great caution because only three transitions were searched for (near 220.5, 143.6 and 103.7 GHz), and for at least one (near 220.5 GHz) there is a severe problem with the line position. Finally, the assumed temperature of 300 K is at odds with the observations carried out toward Sgr B2(N). Thus, further confirming transitions are needed to establish the first detection of glycolaldehyde outside the Galactic center.	+	with the IRAM Plateau de Bure Interferometer toward the high mass star-forming region G31.41+0.31 should be viewed with great caution because only three transitions were searched for (near 220.5, 143.6 and 103.7 GHz), and for at least one (near 220.5 GHz) there is a severe problem with the line position. Finally, the assumed temperature of 300 K is at odds with the observations carried out toward Sgr B2(N). Thus, further confirming transitions are needed to establish the first detection of glycolaldehyde outside the Galactic center.\\

	The situation is more favorable in\\		The situation is more favorable in\\
Line 46:		Line 46:
	by J. K. Jørgensen, C. Favre, S. E. Bisschop, T. L. Bourke, E. F. van Dishoeck, and Markus Schmalzl,\\		by J. K. Jørgensen, C. Favre, S. E. Bisschop, T. L. Bourke, E. F. van Dishoeck, and Markus Schmalzl,\\
	//Astrophys. J.// 757, Art. No. L4 (2012).\\		//Astrophys. J.// 757, Art. No. L4 (2012).\\
-	6 emission features were observed in a small frequency region near 200 GHz toward source B of IRAS 16293-2422. Though two of the featueres are very weak and at least two are blended, the situation is much more favorable than the one described in the previous paragraph – even if one takes into account that several other features remained unassigned. A rotational temperature of about 300 K was estimated for glycolaldehyde as well as for its isomer methyl formate, which has a column density slightly more than one order of magnitude higher than that of glycolaldehyde. The two molecules were also seen toward source A with similar column densities as in source B, but with a rotational temperature estimated at about 200 K. Moreover, several additional features were seen near 700 GHz red-shifted and in absorption toward source B; slightly off source, the same lines were seen unshifted in emission. This was interpreted as a sign of infall.	+	6 emission features were observed in a small frequency region near 200 GHz toward source B of IRAS 16293-2422. Though two of the featueres are very weak and at least two are blended, the situation is much more favorable than the one described in the previous paragraph – even if one takes into account that several other features remained unassigned. A rotational temperature of about 300 K was estimated for glycolaldehyde as well as for its isomer methyl formate, which has a column density slightly more than one order of magnitude higher than that of glycolaldehyde. The two molecules were also seen toward source A with similar column densities as in source B, but with a rotational temperature estimated at about 200 K. Moreover, several additional features were seen near 700 GHz red-shifted and in absorption toward source B; slightly off source, the same lines were seen unshifted in emission. This was interpreted as a sign of infall.\\
		+	This work also reports the identification of three lines attributed to //v//<sub>18</sub> = 1 and one line to //v//<sub>12</sub> = 1; the first identification is probably fairly secure, the second should be viewed with more caution.\\

	J. K. Jørgensen, M. H. D. van der Wiel, A. Coutens, J. M. Lykke, H. S. P. Müller, E. F. van Dishoeck, H. Calcutt, P. Bjerkeli, T. L. Bourke, M. N. Drozdovskaya, C. Favre, E. C. Fayolle, R. T. Garrod, S. K. Jacobsen, K. I. Öberg, M. V. Persson, and S. F. Wampfler\\		J. K. Jørgensen, M. H. D. van der Wiel, A. Coutens, J. M. Lykke, H. S. P. Müller, E. F. van Dishoeck, H. Calcutt, P. Bjerkeli, T. L. Bourke, M. N. Drozdovskaya, C. Favre, E. C. Fayolle, R. T. Garrod, S. K. Jacobsen, K. I. Öberg, M. V. Persson, and S. F. Wampfler\\
Line 57:		Line 59:
	----		----

-	Contributor(s): H. S. P. Müller; 09, 2003; 09, 2004; 02, 2006; 04, 2012; 07, 2012; 09, 2012; 11, 2016	+	Contributor(s): H. S. P. Müller; 09, 2003; 09, 2004; 02, 2006; 04, 2012; 07, 2012; 09, 2012; 11, 2016; 06, 2021

	----		----

2019/02/25 22:38		current
Line 5:		Line 5:
	The first member of this group, not really qualifying for "poly", acetylene, HC<sub>2</sub>H, itself, was detected in absorption at Kitt Peak toward the circumstellar shell of CW Leo, aka IRC +10216. The unresolved //Q//-branch of the ν<sub>4</sub> + ν<sub>5</sub> band was detected at 4091.0 cm<sup>–1</sup> by:\\		The first member of this group, not really qualifying for "poly", acetylene, HC<sub>2</sub>H, itself, was detected in absorption at Kitt Peak toward the circumstellar shell of CW Leo, aka IRC +10216. The unresolved //Q//-branch of the ν<sub>4</sub> + ν<sub>5</sub> band was detected at 4091.0 cm<sup>–1</sup> by:\\
	S. T. Ridgway, D. N. B. Hall, R. S. Wojslaw, S. G. Kleinmann, and D. A. Weinberger,\\		S. T. Ridgway, D. N. B. Hall, R. S. Wojslaw, S. G. Kleinmann, and D. A. Weinberger,\\
-	[[http://dx.doi.org/10.1038/264345a0\|Circumstellar Acetylene in the Infrared Spectrum of IRC +10<sup>o</sup>216]]\\	+	[[https://doi.org/10.1038/264345a0\|Circumstellar Acetylene in the Infrared Spectrum of IRC +10<sup>o</sup>216]]\\
	//Nature// 264, 345–346 (1976).		//Nature// 264, 345–346 (1976).

	A brief account on the observation of the ν<sub>5</sub> band with an origin at 730.3 cm<sup>–1</sup> (or 13.7 μm) was given by:\\		A brief account on the observation of the ν<sub>5</sub> band with an origin at 730.3 cm<sup>–1</sup> (or 13.7 μm) was given by:\\
	T. Kostiuk, F. Espenak, D. Deming, M. J. Mumma, D. Zipoy, and J. Keady,\\		T. Kostiuk, F. Espenak, D. Deming, M. J. Mumma, D. Zipoy, and J. Keady,\\
-	[[http://adsabs.harvard.edu/abs/1985BAAS...17..570K\|Study of Velocity Structure in IRC +10216 Using Acetylene Line Profiles]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1985BAAS...17..570K\|Study of Velocity Structure in IRC +10216 Using Acetylene Line Profiles]]\\
	//Bull. Am. Astron. Soc.// 17, 570 (1985).		//Bull. Am. Astron. Soc.// 17, 570 (1985).

	Hot band transitions associated with ν<sub>5</sub> band, i.e. ν<sub>4</sub> + ν<sub>5</sub> – ν<sub>4</sub> and 2ν<sub>5</sub> – ν<sub>5</sub>, were reported by:\\		Hot band transitions associated with ν<sub>5</sub> band, i.e. ν<sub>4</sub> + ν<sub>5</sub> – ν<sub>4</sub> and 2ν<sub>5</sub> – ν<sub>5</sub>, were reported by:\\
	J. J. Keady and S. T. Ridgway,\\		J. J. Keady and S. T. Ridgway,\\
-	[[http://adsabs.harvard.edu/abs/1993ApJ...406..199K\|The IRC +10216 Circumstellar Envelope. III – Infrared Molecular Line Profiles]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1993ApJ...406..199K\|The IRC +10216 Circumstellar Envelope. III – Infrared Molecular Line Profiles]]\\
	//Astrophys. J.// 406, 199–214 (1993).		//Astrophys. J.// 406, 199–214 (1993).

	The molecule was also detected toward three IR sources embedded in molecular clouds with the NASA IRTF 3 m telescope. Two or three of the //R//(5), //R//(10), or the unresolved //Q//-branch of the ν<sub>5</sub> band were detected toward GL 2591, W3 IRS 5, and OMC-1 IRc2 by\\		The molecule was also detected toward three IR sources embedded in molecular clouds with the NASA IRTF 3 m telescope. Two or three of the //R//(5), //R//(10), or the unresolved //Q//-branch of the ν<sub>5</sub> band were detected toward GL 2591, W3 IRS 5, and OMC-1 IRc2 by\\
	J. H. Lacy, N. J. Evans II, J. M. Achtermann, D. E. Bruce, J. F. Arens, and J. S. Carr,\\		J. H. Lacy, N. J. Evans II, J. M. Achtermann, D. E. Bruce, J. F. Arens, and J. S. Carr,\\
-	[[http://adsabs.harvard.edu/abs/1989ApJ...342L..43L\|Discovery of Interstellar Acetylene]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1989ApJ...342L..43L\|Discovery of Interstellar Acetylene]]\\
	//Astrophys. J.// 383, 674–692 (1991).		//Astrophys. J.// 383, 674–692 (1991).

	The observations were extended to more line of this band, to the same band of H<sup>13</sup>CCH, and to the ν<sub>4</sub> + ν<sub>5</sub> band at 7.6 μm toward OMC-1 using the same facility:\\		The observations were extended to more line of this band, to the same band of H<sup>13</sup>CCH, and to the ν<sub>4</sub> + ν<sub>5</sub> band at 7.6 μm toward OMC-1 using the same facility:\\
	N. J. Evans II, J. H. Lacy, and J. S. Carr,\\		N. J. Evans II, J. H. Lacy, and J. S. Carr,\\
-	[[http://adsabs.harvard.edu/abs/1991ApJ...383..674E\|Infrared Molecular Spectroscopy toward the Orion IRc2 and IRc7 Sources – A new Probe of Physical Conditions and Abundances in Molecular Clouds]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1991ApJ...383..674E\|Infrared Molecular Spectroscopy toward the Orion IRc2 and IRc7 Sources – A new Probe of Physical Conditions and Abundances in Molecular Clouds]]\\
	//Astrophys. J.// 342, L43–L46 (1989).		//Astrophys. J.// 342, L43–L46 (1989).

Line 31:		Line 31:

	J. Cernicharo, A. M. Heras, A. G. G. M. Tielens, J. R. Pardo, F. Herpin, M. Guélin, and L. B. F. M. Waters,\\		J. Cernicharo, A. M. Heras, A. G. G. M. Tielens, J. R. Pardo, F. Herpin, M. Guélin, and L. B. F. M. Waters,\\
-	[[http://dx.doi.org/10.1086/318871\|//Infrared Space Observatory's// Discovery of C<sub>4</sub>H<sub>2</sub>, C<sub>6</sub>H<sub>2</sub>, and Benzene in CRL 618]]\\	+	[[https://doi.org/10.1086/318871\|//Infrared Space Observatory's// Discovery of C<sub>4</sub>H<sub>2</sub>, C<sub>6</sub>H<sub>2</sub>, and Benzene in CRL 618]]\\
	//Astrophys. J.// 546, L123–L126 (2001);\\		//Astrophys. J.// 546, L123–L126 (2001);\\
	report the detection of butadiyne, HC<sub>4</sub>H, aka diacetylene, and hexatriyne, HC<sub>6</sub>H, aka as triacetylene, employing mid-infrared absorption spectroscopy. The unresolved //Q//-branches of the cold ν<sub>8</sub> band of butadiyne along with hot bands were detected at 15.9 μm. Close by, at 16.1 μm, the //Q//-branch of ν<sub>11</sub> band of hexatriyne is seen.		report the detection of butadiyne, HC<sub>4</sub>H, aka diacetylene, and hexatriyne, HC<sub>6</sub>H, aka as triacetylene, employing mid-infrared absorption spectroscopy. The unresolved //Q//-branches of the cold ν<sub>8</sub> band of butadiyne along with hot bands were detected at 15.9 μm. Close by, at 16.1 μm, the //Q//-branch of ν<sub>11</sub> band of hexatriyne is seen.
Line 37:		Line 37:
	A separate report;\\		A separate report;\\
	J. Cernicharo, A. M. Heras, J. R. Pardo, A. G. G. M. Tielens, M. Guélin, E. Dartois, R. Neri, and L. B. F. M. Waters;\\		J. Cernicharo, A. M. Heras, J. R. Pardo, A. G. G. M. Tielens, M. Guélin, E. Dartois, R. Neri, and L. B. F. M. Waters;\\
-	[[http://dx.doi.org/10.1086/318872\|Methylpolyynes and Small Hydrocarbons in CRL 618]]\\	+	[[https://doi.org/10.1086/318872\|Methylpolyynes and Small Hydrocarbons in CRL 618]]\\
	//Astrophys. J.// 546, L127–L130 (2001);\\		//Astrophys. J.// 546, L127–L130 (2001);\\
	identifies one combination band each for butadiyne and hexatriyne. The spectrum around 8 μm is rather complex as is the model which contains many species. Inspection of laboratory spectroscopic literature is useful. A complex feature at almost exactly 8 μm is largely attributable to the strong, unresolved //R//-branch of ν<sub>6</sub> + ν<sub>8</sub> band of butadiyne. Features at 8.08 and 8.14 μm can be attributed to the unresolved //R//- and //P//-branches of the respective strong ν<sub>8</sub> + ν<sub>11</sub> band of hexatriyne, both overlapping the //P//-branch of the butadiyne band.		identifies one combination band each for butadiyne and hexatriyne. The spectrum around 8 μm is rather complex as is the model which contains many species. Inspection of laboratory spectroscopic literature is useful. A complex feature at almost exactly 8 μm is largely attributable to the strong, unresolved //R//-branch of ν<sub>6</sub> + ν<sub>8</sub> band of butadiyne. Features at 8.08 and 8.14 μm can be attributed to the unresolved //R//- and //P//-branches of the respective strong ν<sub>8</sub> + ν<sub>11</sub> band of hexatriyne, both overlapping the //P//-branch of the butadiyne band.
Line 43:		Line 43:
	The spectral same region was also studied under high resolution by:\\		The spectral same region was also studied under high resolution by:\\
	J. P. Fonfría, J. Cernicharo, M. J. Richter, J. H. Lacy,\\		J. P. Fonfría, J. Cernicharo, M. J. Richter, J. H. Lacy,\\
-	[[http://dx.doi.org/10.1088/0004-637X/728/1/43\|The Abundances of Polyacetylenes towards CRL618]]\\	+	[[https://doi.org/10.1088/0004-637X/728/1/43\|The Abundances of Polyacetylenes towards CRL618]]\\
	//Astrophys. J.// 728, Art. No. 43 (2011),\\		//Astrophys. J.// 728, Art. No. 43 (2011),\\
	revealing clear evidence for several hot bands associated with these rather strong combination bands.\\		revealing clear evidence for several hot bands associated with these rather strong combination bands.\\
Line 50:		Line 50:
	Earlier, the two fundamental vibrations ν<sub>8</sub> of butadiyne at 15.9 μm and of ν<sub>11</sub> of hexatriyne at 16.1 μm, see also above, were observed toward a Nova like star by\\		Earlier, the two fundamental vibrations ν<sub>8</sub> of butadiyne at 15.9 μm and of ν<sub>11</sub> of hexatriyne at 16.1 μm, see also above, were observed toward a Nova like star by\\
	A. Evans, V. H. Tyne, J. Th. van Loon, B. Smalley, T. R. Geballe, R. D. Gehrz, C. E. Woodward, A. A. Zijlstra, E. Polomski, M. T. Rushton, S. P. S. Eyres, S. G. Starrfield, J. Krautter, and R. M. Wagner,\\		A. Evans, V. H. Tyne, J. Th. van Loon, B. Smalley, T. R. Geballe, R. D. Gehrz, C. E. Woodward, A. A. Zijlstra, E. Polomski, M. T. Rushton, S. P. S. Eyres, S. G. Starrfield, J. Krautter, and R. M. Wagner,\\
-	[[http://dx.doi.org/10.1111/j.1745-3933.2006.00246.x\|The //Spitzer// Infrared Spectrometer View of V4334 Sgr (Sakurai’s Object)]]\\	+	[[https://doi.org/10.1111/j.1745-3933.2006.00246.x\|The //Spitzer// Infrared Spectrometer View of V4334 Sgr (Sakurai’s Object)]]\\
	//Mon. Not. R. Astron. Soc.// 373, L75–L79 (2006).		//Mon. Not. R. Astron. Soc.// 373, L75–L79 (2006).

Line 57:		Line 57:

	Contributor(s): H. S. P. Müller; 10, 2003; 01, 2011; 06, 2011		Contributor(s): H. S. P. Müller; 10, 2003; 01, 2011; 06, 2011
-

	----		----

2019/04/29 17:18		current
Line 3:		Line 3:
	L. W. Avery, N. W. Broten, J. M. McLeod, T. Oka, and H. W. Kroto\\		L. W. Avery, N. W. Broten, J. M. McLeod, T. Oka, and H. W. Kroto\\
	reported on the\\		reported on the\\
-	[[http://cdsads.u-strasbg.fr/abs/1976ApJ...205L.173A\|Detection of the Heavy Interstellar Molecule Cyanodiacetylene]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1976ApJ...205L.173A\|Detection of the Heavy Interstellar Molecule Cyanodiacetylene]]\\
	//Astrophys. J.// 205, L173–L175 (1976).\\		//Astrophys. J.// 205, L173–L175 (1976).\\
	The //J// = 4 – 3 transition near 10.651 GHz was observed in emission toward Sagittarius (Sgr) B2 employing the 46 m radio telecope of the Algonquin Radio Observatory.		The //J// = 4 – 3 transition near 10.651 GHz was observed in emission toward Sagittarius (Sgr) B2 employing the 46 m radio telecope of the Algonquin Radio Observatory.
Line 9:		Line 9:
	N. W. Broten, J. M. McLeod, T. Oka, L. W. Avery, J. W. Brooks, R. X. McGee, and L. M. Newton\\		N. W. Broten, J. M. McLeod, T. Oka, L. W. Avery, J. W. Brooks, R. X. McGee, and L. M. Newton\\
	reported subsequently on\\		reported subsequently on\\
-	[[http://cdsads.u-strasbg.fr/abs/1976ApJ...209L.143B\|Evidence for Weak Maser Action in Interstellar Cyanodiacetylene]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1976ApJ...209L.143B\|Evidence for Weak Maser Action in Interstellar Cyanodiacetylene]]\\
	//Astrophys. J.// 209, L143–L147 (1976).\\		//Astrophys. J.// 209, L143–L147 (1976).\\
	The //J// = 8 – 7 transition near 21.301 GHz was observed toward Sagittarius /Sgr) B2 employing the 46 m radio telecope of the Algonquin Radio Observatory. In addition, the Parkes 64 m dish was used to study the The //J// = 1 – 0 transition near 2.663 GHz with well-resolved hyperfine structure. The high intensity of the latter emission lines were viewed as evidence for weak maser activity.		The //J// = 8 – 7 transition near 21.301 GHz was observed toward Sagittarius /Sgr) B2 employing the 46 m radio telecope of the Algonquin Radio Observatory. In addition, the Parkes 64 m dish was used to study the The //J// = 1 – 0 transition near 2.663 GHz with well-resolved hyperfine structure. The high intensity of the latter emission lines were viewed as evidence for weak maser activity.
Line 21:		Line 21:
	More recently, the Effelsberg 100 m telecope was used to study the circumstellar shell of the famous carbon star CW Leo:\\		More recently, the Effelsberg 100 m telecope was used to study the circumstellar shell of the famous carbon star CW Leo:\\
	G. Winnewisser and C. M. Walmsley,\\		G. Winnewisser and C. M. Walmsley,\\
-	[[http://cdsads.u-strasbg.fr/abs/1978A%26A....70L..37W\|The Detection of HC<sub>5</sub>N and HC<sub>7</sub>N in IRC +10216]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1978A%26A....70L..37W\|The Detection of HC<sub>5</sub>N and HC<sub>7</sub>N in IRC +10216]]\\
	//Astron. Astrophys.// 70, L37–L39 (1978).\\		//Astron. Astrophys.// 70, L37–L39 (1978).\\
	The //J// = 9 – 8 transition near 23.964 GHz was detected for the smaller polyyne.\\		The //J// = 9 – 8 transition near 23.964 GHz was detected for the smaller polyyne.\\
Line 28:		Line 28:
	The detection of DC<sub>5</sub>N in TMC-1 was reported by two groups simultaneously:\\		The detection of DC<sub>5</sub>N in TMC-1 was reported by two groups simultaneously:\\
	J. M. MacLeod, L. W. Avery, and N. W. Broten,\\		J. M. MacLeod, L. W. Avery, and N. W. Broten,\\
-	[[http://cdsads.u-strasbg.fr/abs/1981ApJ...251L..33M\|//Astrophys. J.//]] 251, L33–L36 (1981); and\\	+	[[https://ui.adsabs.harvard.edu/abs/1981ApJ...251L..33M\|//Astrophys. J.//]] 251, L33–L36 (1981); and\\
	F. P. Schloerb, R. L. Snell, W. D. Langer, and J. S. Young,\\		F. P. Schloerb, R. L. Snell, W. D. Langer, and J. S. Young,\\
	[[http://cdsads.u-strasbg.fr/abs/1981ApJ...251L..37S\|//Astrophys. J.//]] 251, L37–L41 (1981).\\		[[http://cdsads.u-strasbg.fr/abs/1981ApJ...251L..37S\|//Astrophys. J.//]] 251, L37–L41 (1981).\\
Line 35:		Line 35:
	S. Takano, H. Suzuki, M. Ohishi, S.-I. Ishikawa, N. Kaifu, Y. Hirahara, and A. Masuda\\		S. Takano, H. Suzuki, M. Ohishi, S.-I. Ishikawa, N. Kaifu, Y. Hirahara, and A. Masuda\\
	used the Nobeyama 45 m telescope for the\\		used the Nobeyama 45 m telescope for the\\
-	[[http://adsabs.harvard.edu/abs/1990ApJ...361L..15T\|Detection of Five <sup>13</sup>C Isotopic Species of HC<sub>5</sub>N in TMC-1]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1990ApJ...361L..15T\|Detection of Five <sup>13</sup>C Isotopic Species of HC<sub>5</sub>N in TMC-1]]\\
	//Astrophys. J.// 361, L15–L18 (1990).\\		//Astrophys. J.// 361, L15–L18 (1990).\\
	The //J// = 14 – 13 transitions bewteen 36 and 38 GHz were detected at intensities compatible with the <sup>12</sup>C/<sup>13</sup>C ratio in the solar neighborhood.		The //J// = 14 – 13 transitions bewteen 36 and 38 GHz were detected at intensities compatible with the <sup>12</sup>C/<sup>13</sup>C ratio in the solar neighborhood.
Line 49:		Line 49:
	[[https://doi.org/10.1086/430774\|Observational Evidence of the Formation of Cyanopolyynes in CRL 618 through the Polymerization of HCN]]\\		[[https://doi.org/10.1086/430774\|Observational Evidence of the Formation of Cyanopolyynes in CRL 618 through the Polymerization of HCN]]\\
	//Astrophys. J.// 628, 275–282 (2005).\\		//Astrophys. J.// 628, 275–282 (2005).\\
-	Four low-lying states (//v//<sub>11</sub> = 1 to 3 and //v//<sub>10</sub> = 1) were detected with vibrational energies of up to about 315 <sup>–1</sup>.	+	Four low-lying states (//v//<sub>11</sub> = 1 to 3 and //v//<sub>10</sub> = 1) were detected with vibrational energies of up to about 315 cm<sup>–1</sup>.


Line 55:		Line 55:

	Contributor(s): H. S. P. Müller; 01, 2018.		Contributor(s): H. S. P. Müller; 01, 2018.
-

	----		----

2019/02/25 22:38		current
Line 3:		Line 3:
	D. T. Halfen, V. V. Ilyushin, and L. M. Ziurys,\\		D. T. Halfen, V. V. Ilyushin, and L. M. Ziurys,\\
	reported on the\\		reported on the\\
-	[[http://dx.doi.org/10.1088/2041-8205/812/1/L5\|Interstellar Detection of Methyl Isocyanate CH<sub>3</sub>NCO in Sgr B2(N): A Link from Molecular Clouds to Comets]]\\	+	[[https://doi.org/10.1088/2041-8205/812/1/L5\|Interstellar Detection of Methyl Isocyanate CH<sub>3</sub>NCO in Sgr B2(N): A Link from Molecular Clouds to Comets]]\\
	//Astrophys. J.// 812, Art. No. L5 (2015).\\		//Astrophys. J.// 812, Art. No. L5 (2015).\\
	Several clear, slightly, and heavily blended features were detected in emission in a molecular line survey of Sagittarius B2(N) in the 4 and 3 mm wavelength region using the 12 m ARO dish. The molecule occurs in both main hot cores with similar column densities at rotational temperatures of about 25 K. It is less abundant than HNCO by about factors of 35 and 53.		Several clear, slightly, and heavily blended features were detected in emission in a molecular line survey of Sagittarius B2(N) in the 4 and 3 mm wavelength region using the 12 m ARO dish. The molecule occurs in both main hot cores with similar column densities at rotational temperatures of about 25 K. It is less abundant than HNCO by about factors of 35 and 53.

-	J. Cernicharo1, Z. Kisiel, B. Tercero, L. Kolesniková, I. R. Medvedev, A. López, S. Fortman, M. Winnewisser, F. C. de Lucia, J. L. Alonso, and J.-C. Guillemin,\\	+	J. Cernicharo, Z. Kisiel, B. Tercero, L. Kolesniková, I. R. Medvedev, A. López, S. Fortman, M. Winnewisser, F. C. de Lucia, J. L. Alonso, and J.-C. Guillemin,\\
	reported on the\\		reported on the\\
-	[[http://dx.doi.org/10.1051/0004-6361/201527531\|A Rigorous Detection of Interstellar CH<sub>3</sub>NCO: An important Missing Species in Astrochemical Networks]]\\	+	[[https://doi.org/10.1051/0004-6361/201527531\|A Rigorous Detection of Interstellar CH<sub>3</sub>NCO: An important Missing Species in Astrochemical Networks]]\\
	//Astron. Astrophys.// 587, Art. No. L4 (2016).\\		//Astron. Astrophys.// 587, Art. No. L4 (2016).\\
	Using extensive Orion KL molecular line survey data obtained with the IRAM 30 m telescope as well as ALMA Cycle 0 science verification data, the authors identified a plethora of transitions and characterized the physcal conditions.\\		Using extensive Orion KL molecular line survey data obtained with the IRAM 30 m telescope as well as ALMA Cycle 0 science verification data, the authors identified a plethora of transitions and characterized the physcal conditions.\\
	Using the meanwhile public IRAM 30 m data on Sagittarius B2 from\\		Using the meanwhile public IRAM 30 m data on Sagittarius B2 from\\
	A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\		A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\
-	[[http://dx.doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\	+	[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\
	//Astron. Astrophys.// 559, Art. No. A47 (2013);\\		//Astron. Astrophys.// 559, Art. No. A47 (2013);\\
	the authors also corrected and added assignments from the first paper and reanalyzed the physical conditions in that source. They find methynol, HNCO, and methyl cyanide to be more abundant in Sgr B2(N) by factors of about 40, 40, and 50, different from the two positions in Orion KL: 400, 15, and 10 for position A, and 200, 15, and 25 for position B.		the authors also corrected and added assignments from the first paper and reanalyzed the physical conditions in that source. They find methynol, HNCO, and methyl cyanide to be more abundant in Sgr B2(N) by factors of about 40, 40, and 50, different from the two positions in Orion KL: 400, 15, and 10 for position A, and 200, 15, and 25 for position B.

2019/02/25 22:38		current
Line 1:		Line 1:
	===== Detections of Metal Isocyanides and Metal Cyanides in Circumstellar Envelopes =====		===== Detections of Metal Isocyanides and Metal Cyanides in Circumstellar Envelopes =====

-	Magnesium isocyanide, MgNC, is a linear radical which is lower in energy than its MgCN isomer. It was observed first as an unidentified species in the circumstellar envelope of the famous carbon star CW Leo, also known as IRC +10216, by\\	+	==== MgNC ====
		+
		+	Magnesium isocyanide is a linear radical which is lower in energy than its MgCN isomer. It was observed first as an unidentified species in the circumstellar envelope of the famous carbon star CW Leo, also known as IRC +10216, by\\
	M. Guélin, J. Cernicharo, C. Kahane, E. González-Alfonso,\\		M. Guélin, J. Cernicharo, C. Kahane, E. González-Alfonso,\\
-	[[http://adsabs.harvard.edu/abs/1986A%26A...157L..17G\|A New Free Radical in IRC +10216]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1986A%26A...157L..17G\|A New Free Radical in IRC +10216]]\\
	//Astron. Astrophys.// 157, L17–L20 (1986).\\		//Astron. Astrophys.// 157, L17–L20 (1986).\\
	The authors detected in the 3 mm region both strong fine structure components of the //N"// = 6, 7, and 8 transitions. The authors proposed as most likely carriers HSiCC, its isomer HCCSi, or HSCC.		The authors detected in the 3 mm region both strong fine structure components of the //N"// = 6, 7, and 8 transitions. The authors proposed as most likely carriers HSiCC, its isomer HCCSi, or HSCC.
Line 9:		Line 11:
	The molecule was identified few years later as MgNC via masurement of its rotational spectrum by:\\		The molecule was identified few years later as MgNC via masurement of its rotational spectrum by:\\
	K. Kawaguchi, E. Kagi, T. Hirano, S. Takano, S. Saito,\\		K. Kawaguchi, E. Kagi, T. Hirano, S. Takano, S. Saito,\\
-	[[http://adsabs.harvard.edu/abs/1993ApJ...406L..39K\|Laboratory Spectroscopy of MgNC – The First Radioastronomical Identification of Mg-bearing Molecule]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1993ApJ...406L..39K\|Laboratory Spectroscopy of MgNC – The First Radioastronomical Identification of Mg-bearing Molecule]]\\
	//Astrophys. J.// 406, L39–L42 (1993).		//Astrophys. J.// 406, L39–L42 (1993).

	Besides the main isotope of Mg with the mass number 24, there are two stable isotopes with mass numbers 25 and 26, respectively. The corresponding isotopologs have both been detected toward CW Leo by:\\		Besides the main isotope of Mg with the mass number 24, there are two stable isotopes with mass numbers 25 and 26, respectively. The corresponding isotopologs have both been detected toward CW Leo by:\\
	M. Guélin, M. Forstini, P. Valiron, L. M. Ziurys, M. A. Anderson, J. Cernicharo, and C. Kahane,\\		M. Guélin, M. Forstini, P. Valiron, L. M. Ziurys, M. A. Anderson, J. Cernicharo, and C. Kahane,\\
-	[[http://adsabs.harvard.edu/abs/1995A%26A...297..183G\|Nucleosynthesis in AGB Stars: Observation of <sup>25</sup>Mg and <sup>26</sup>Mg in IRC +10216 and Possible Detection of <sup>26</sup>Al]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1995A%26A...297..183G\|Nucleosynthesis in AGB Stars: Observation of <sup>25</sup>Mg and <sup>26</sup>Mg in IRC +10216 and Possible Detection of <sup>26</sup>Al]]\\
	//Astron. Astrophys.// 297, 183–196 (1995).\\		//Astron. Astrophys.// 297, 183–196 (1995).\\

Line 20:		Line 22:
	More recently, MgNC was also detected toward the protoplanetary nebula (PPN) CRL 2688, the egg nebula:\\		More recently, MgNC was also detected toward the protoplanetary nebula (PPN) CRL 2688, the egg nebula:\\
	J. L. Highberger, C. Savage, J. H. Bieging, L. M. Ziurys,\\		J. L. Highberger, C. Savage, J. H. Bieging, L. M. Ziurys,\\
-	[[http://dx.**doi.org/10.1086/323231\|Heavy-Metal Chemistry in Proto-Planetary Nebulae:\\	+	[[https**://doi.org/10.1086/323231\|Heavy-Metal Chemistry in Proto-Planetary Nebulae:\\
	Detection of MgNC, NaCN, and AlF toward CRL 2688]]**\\		Detection of MgNC, NaCN, and AlF toward CRL 2688]]**\\
	//Astrophys. J.// 562, 790–798 (2001).		//Astrophys. J.// 562, 790–798 (2001).
Line 27:		Line 29:
	----		----

-	Sodium cyanide, NaCN, is a nearly T-shaped molecule. It possesses a NaN bond that is slightly shorther than the NaC bond. Therefore, the molecule should be considered more appropriately as sodium isocyanide, NaNC. It was observed first in the circumstellar envelope of CW Leo in four //K<sub>a</sub>// = 0 transitions by\\	+	==== NaCN ====
		+
		+	Sodium cyanide is a nearly T-shaped molecule. It possesses a NaN bond that is slightly shorther than the NaC bond. Therefore, the molecule should be considered more appropriately as sodium isocyanide, NaNC. It was observed first in the circumstellar envelope of CW Leo in four //K<sub>a</sub>// = 0 transitions by\\
	B. E. Turner, T. C. Steimle, and L. Meerts,\\		B. E. Turner, T. C. Steimle, and L. Meerts,\\
-	[[http://adsabs.harvard.edu/abs/1994ApJ...426L..97T\|Detection of Sodium Cyanide (NaCN) in IRC+10216]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1994ApJ...426L..97T\|Detection of Sodium Cyanide (NaCN) in IRC+10216]]\\
	//Astrophys. J.// 426, 97–100 (1994).\\		//Astrophys. J.// 426, 97–100 (1994).\\
	The //J"// = 4, 5, and 6 transitions are in the 3 mm region, the one with //J"// = 8 is in the 2 mm region. Note: in that paper the assumed dipole moment was too low by a factor of about 2.5 because an //ab initio// dipole moment was taken as being in units of Debye whereas it actually was given in atomic units. 1 au equals 2.542 D.		The //J"// = 4, 5, and 6 transitions are in the 3 mm region, the one with //J"// = 8 is in the 2 mm region. Note: in that paper the assumed dipole moment was too low by a factor of about 2.5 because an //ab initio// dipole moment was taken as being in units of Debye whereas it actually was given in atomic units. 1 au equals 2.542 D.
Line 35:		Line 39:
	NaCN too was detected toward the PPN CRL 2688:\\		NaCN too was detected toward the PPN CRL 2688:\\
	J. L. Highberger, C. Savage, J. H. Bieging, L. M. Ziurys,\\		J. L. Highberger, C. Savage, J. H. Bieging, L. M. Ziurys,\\
-	[[http://dx.**doi.org/10.1086/323231\|Heavy-Metal Chemistry in Proto-Planetary Nebulae:\\	+	[[https**://doi.org/10.1086/323231\|Heavy-Metal Chemistry in Proto-Planetary Nebulae:\\
	Detection of MgNC, NaCN, and AlF toward CRL 2688]]**\\		Detection of MgNC, NaCN, and AlF toward CRL 2688]]**\\
	//Astrophys. J.// 562, 790–798 (2001).		//Astrophys. J.// 562, 790–798 (2001).
Line 42:		Line 46:
	----		----

-	The magnesium cyanide isomer, MgCN, was detected in three transitions with //N"// = 8, 9, and 10, all lying in the 3 mm region, by:\\	+	==== MgCN ====
		+
		+	The magnesium cyanide isomer was detected in three transitions with //N"// = 8, 9, and 10, all lying in the 3 mm region, by:\\
	L. M. Ziurys, A. J. Apponi, M. Guélin, and J. Cernicharo,\\		L. M. Ziurys, A. J. Apponi, M. Guélin, and J. Cernicharo,\\
-	[[http://adsabs.harvard.edu/abs/1995ApJ...445L..47Z\|Detection of MgCN in IRC +10216: A New Metal-bearing Free Radical]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1995ApJ...445L..47Z\|Detection of MgCN in IRC +10216: A New Metal-bearing Free Radical]]\\
	//Astrophys. J.// 445, L47–L50 (1995).		//Astrophys. J.// 445, L47–L50 (1995).

Line 50:		Line 56:
	----		----

-	Aluminum isocyanide, AlNC, is a linear molecule which is lower in energy than its AlCN isomer. It was observed in five transitions (//J"// = 10, 11, and 12 in the 2 mm region and //J"// = 17 and 20 in the 1 mm region) toward CW Leo by:\\	+	==== AlNC ====
		+
		+	Aluminum isocyanide is a linear molecule which is lower in energy than its AlCN isomer. It was observed in five transitions (//J"// = 10, 11, and 12 in the 2 mm region and //J"// = 17 and 20 in the 1 mm region) toward CW Leo by:\\
	L. M. Ziurys, C. Savage, J. L. Highberger, A. J. Apponi, M. Guélin, and J. Cernicharo,\\		L. M. Ziurys, C. Savage, J. L. Highberger, A. J. Apponi, M. Guélin, and J. Cernicharo,\\
-	[[http://dx.doi.org/10.1086/338775\|More Metal Cyanide Species: Detection of AlNC (X <sup>1</sup>Σ<sup>+</sup>) toward IRC +10216]]\\	+	[[https://doi.org/10.1086/338775\|More Metal Cyanide Species: Detection of AlNC (X <sup>1</sup>Σ<sup>+</sup>) toward IRC +10216]]\\
	//Astrophys. J.// 564, L45–L48 (2002).		//Astrophys. J.// 564, L45–L48 (2002).

Line 58:		Line 66:
	----		----

-	Potassium cyanide, KCN, is a nearly T-shaped molecule, just as NaCN. It too should be considered as an isocyanide rather than a cyanide. Several transitions in the 3, 2, and 1 mm region were detected toward CW Leo by:\\	+	==== KCN ====
		+
		+	Potassium cyanide is a nearly T-shaped molecule, just as NaCN. It too should be considered as an isocyanide rather than a cyanide. Several transitions in the 3, 2, and 1 mm region were detected toward CW Leo by:\\
	R. L. Pulliam, C. Savage, M. Agúndez, J. Cernicharo, M. Guélin, and L. M. Ziurys,\\		R. L. Pulliam, C. Savage, M. Agúndez, J. Cernicharo, M. Guélin, and L. M. Ziurys,\\
-	[[http://dx.doi.org/10.1088/2041-8205/725/2/L181\|Identification of KCN in IRC +10216: Evidence for Selective Cyanide Chemistry]]\\	+	[[https://doi.org/10.1088/2041-8205/725/2/L181\|Identification of KCN in IRC +10216: Evidence for Selective Cyanide Chemistry]]\\
	//Astrophys. J.// 725, L181–L185 (2010).		//Astrophys. J.// 725, L181–L185 (2010).

Line 66:		Line 76:
	----		----

-	Iron cyanide, FeCN, is a linear molecule. According to laboratory spectroscopic work, it actually is lowein in energy than iron isocyanide, FeNC. The molecule has a <sup>4</sup>Δ<sub>i</sub> ground state with considerable spin-orbit splitting. The Ω = 7/2 spin component is lowest in energy. Three apparently clean transitions with //J"// = 9.5, 11.5, and 12.5 as well as two partially overlapped transitions (10.5 and 15.5) were detected with the ARO 12 m radio-telescope toward CW Leo by:\\	+	==== FeCN ====
		+
		+	Iron cyanide is a linear molecule. According to laboratory spectroscopic work, it actually is lowein in energy than iron isocyanide, FeNC. The molecule has a <sup>4</sup>Δ<sub>i</sub> ground state with considerable spin-orbit splitting. The Ω = 7/2 spin component is lowest in energy. Three apparently clean transitions with //J"// = 9.5, 11.5, and 12.5 as well as two partially overlapped transitions (10.5 and 15.5) were detected with the ARO 12 m radio-telescope toward CW Leo by:\\
	L. N. Zack, D. T. Halfen, and L. M. Ziurys,\\		L. N. Zack, D. T. Halfen, and L. M. Ziurys,\\
-	[[http://dx.doi.org/10.1088/2041-8205/733/2/L36\|Detection of FeCN (//X// <sup>4</sup>Δ<sub>i</sub>) in IRC +10216: A New Interstellar Molecule]]\\	+	[[https://doi.org/10.1088/2041-8205/733/2/L36\|Detection of FeCN (//X// <sup>4</sup>Δ<sub>i</sub>) in IRC +10216: A New Interstellar Molecule]]\\
	//Astrophys. J.// 733, Art. No. L36 (2011).		//Astrophys. J.// 733, Art. No. L36 (2011).

Line 75:		Line 87:

	Contributor(s): H. S. P. Müller; 09, 2005; 04, 2007; 04, 2011; 05, 2011		Contributor(s): H. S. P. Müller; 09, 2005; 04, 2007; 04, 2011; 05, 2011
-

	----		----

2019/02/25 22:38		current
Line 3:		Line 3:
	The //N// = 1 – 0, //J// = 0 – 1, fine structure component of oxidaniumylidene or hydroxylium, OH<sup>+</sup>, near 909 GHz has recently been detected in absorption from ground with the APEX 12 m telescope toward the evolved massive star-forming region Sagittarius B2(M):\\		The //N// = 1 – 0, //J// = 0 – 1, fine structure component of oxidaniumylidene or hydroxylium, OH<sup>+</sup>, near 909 GHz has recently been detected in absorption from ground with the APEX 12 m telescope toward the evolved massive star-forming region Sagittarius B2(M):\\
	F. Wyrowski, K. M. Menten, R. Güsten, and A. Belloche\\		F. Wyrowski, K. M. Menten, R. Güsten, and A. Belloche\\
-	[[http://dx.doi.org/10.1051/0004-6361/201014364\|First Interstellar Detection of OH<sup>+</sup>]]\\	+	[[https://doi.org/10.1051/0004-6361/201014364\|First Interstellar Detection of OH<sup>+</sup>]]\\
	//Astron. Astrophys.// 518, (2010), Art. No. A26.\\		//Astron. Astrophys.// 518, (2010), Art. No. A26.\\
	Interestingly, this is the weakest of the three fine structure components.		Interestingly, this is the weakest of the three fine structure components.
Line 9:		Line 9:
	More recently, the strongest fine structure component near 972 GHz has been detected with the //Herschel// satellite toward several other sources, in particular toward W31C (G10.6–0.4), also in absorption:\\		More recently, the strongest fine structure component near 972 GHz has been detected with the //Herschel// satellite toward several other sources, in particular toward W31C (G10.6–0.4), also in absorption:\\
	M. Gerin, M. De Luca, J. Black, et al.\\		M. Gerin, M. De Luca, J. Black, et al.\\
-	[[http://dx.doi.org/10.1051/0004-6361/201014576\|Interstellar OH<sup>+</sup>, H<sub>2</sub>O<sup>+</sup> and H<sub>3</sub>O<sup>+</sup> along the Sight-line to G10.6–0.4]]\\	+	[[https://doi.org/10.1051/0004-6361/201014576\|Interstellar OH<sup>+</sup>, H<sub>2</sub>O<sup>+</sup> and H<sub>3</sub>O<sup>+</sup> along the Sight-line to G10.6–0.4]]\\
	//Astron. Astrophys.// 518, (2010) Art. No. L110.\\		//Astron. Astrophys.// 518, (2010) Art. No. L110.\\
	Model calculations were carried out indicating that OH<sup>+</sup> and H<sub>2</sub>O<sup>+</sup> are formed in the mostly atomic diffuse ISM in these sources.		Model calculations were carried out indicating that OH<sup>+</sup> and H<sub>2</sub>O<sup>+</sup> are formed in the mostly atomic diffuse ISM in these sources.
Line 15:		Line 15:
	F. F. S. van der Tak, Z. Nagy, V. Ossenkopf, Z. Makai, J. H. Black, A. Faure, M. Gerin, and E. A. Bergin\\		F. F. S. van der Tak, Z. Nagy, V. Ossenkopf, Z. Makai, J. H. Black, A. Faure, M. Gerin, and E. A. Bergin\\
	report on\\		report on\\
-	[[http://dx.doi.org/10.1051/0004-6361/201322164\|Spatially Extended OH<sup>+</sup> Emission from the Orion Bar and Ridge]]\\	+	[[https://doi.org/10.1051/0004-6361/201322164\|Spatially Extended OH<sup>+</sup> Emission from the Orion Bar and Ridge]]\\
	//Astron. Astrophys.// 560, (2013) Art. No. A95.\\		//Astron. Astrophys.// 560, (2013) Art. No. A95.\\
	OH<sup>+</sup> in emission was also detected toward the Crab Nebula supernova remnant, also known as M 1, by:\\		OH<sup>+</sup> in emission was also detected toward the Crab Nebula supernova remnant, also known as M 1, by:\\
	M. J. Barlow, B. M. Swinyard, P. J. Owen, J. Cernicharo, H. L. Gomez, R. J. Ivison, O. Krause, T. L. Lim, M. Matsuura, S. Miller, G. Olofsson, and E. T. Polehampton,\\		M. J. Barlow, B. M. Swinyard, P. J. Owen, J. Cernicharo, H. L. Gomez, R. J. Ivison, O. Krause, T. L. Lim, M. Matsuura, S. Miller, G. Olofsson, and E. T. Polehampton,\\
-	[[http://dx.doi.org/10.1126/science.1243582\|Detection of a Noble Gas Molecular Ion, <sup>36</sup>ArH<sup>+</sup>, in the Crab Nebula]]\\	+	[[https://doi.org/10.1126/science.1243582\|Detection of a Noble Gas Molecular Ion, <sup>36</sup>ArH<sup>+</sup>, in the Crab Nebula]]\\
	//Science// 342, (2013) 1343.\\		//Science// 342, (2013) 1343.\\
	Both observations were made with the //Herschel// satellite.		Both observations were made with the //Herschel// satellite.
Line 25:		Line 25:
	An unspecified electronic transition at 385.3769 nm or 27903.58 cm<sup>–1</sup> was detected in diffuse clouds toward several stars at ESO Paranal observatory by:\\		An unspecified electronic transition at 385.3769 nm or 27903.58 cm<sup>–1</sup> was detected in diffuse clouds toward several stars at ESO Paranal observatory by:\\
	J. Krelowski, Y. Beletsky, and G. A. Galazutdinov,\\		J. Krelowski, Y. Beletsky, and G. A. Galazutdinov,\\
-	[[http://dx.doi.org/10.1088/2041-8205/719/1/L20\|Hydroxyl Cation in Translucent Interstellar Clouds]]\\	+	[[https://doi.org/10.1088/2041-8205/719/1/L20\|Hydroxyl Cation in Translucent Interstellar Clouds]]\\
	//Astrophys. J.// 719, (2010) L20.\\		//Astrophys. J.// 719, (2010) L20.\\
	This is the //R//(0) origin transition of the //v// = 0 – 0 vibrational band belonging to the //A// – //X// electronic transition which had been investigated by:\\		This is the //R//(0) origin transition of the //v// = 0 – 0 vibrational band belonging to the //A// – //X// electronic transition which had been investigated by:\\
	A. J. Merer, D. N. Malm, R. W. Martin, M. Horani, and J. Rostas,\\		A. J. Merer, D. N. Malm, R. W. Martin, M. Horani, and J. Rostas,\\
-	[[http://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?calyLang=eng&journal=cjp&volume=53&year=0&issue=3&msno=p75-037\|The Ultraviolet Emission Spectra of OH<sup>+</sup> and OD<sup>+</sup>. Rotational Structure and Perturbations in the //A// <sup>3</sup>Π<sub>//i//</sub> – //X// <sup>3</sup>Σ<sup>–</sup> Transition]]\\	+	[[https://doi.org/10.1139/p75-037\|The Ultraviolet Emission Spectra of OH<sup>+</sup> and OD<sup>+</sup>. Rotational Structure and Perturbations in the //A// <sup>3</sup>Π<sub>//i//</sub> – //X// <sup>3</sup>Σ<sup>–</sup> Transition]]\\
-	//Can. J. Phys.// 53, (2010) 251.	+	//Can. J. Phys.// 53, (1975) 251.


Line 36:		Line 36:

	Contributor(s): H. S. P. Müller; 07 & 08, 2010; 12, 2013.		Contributor(s): H. S. P. Müller; 07 & 08, 2010; 12, 2013.
-

	----		----

2019/02/25 22:38		current
Line 3:		Line 3:
	Vinyl cyanide, C<sub>2</sub>H<sub>3</sub>CN, aka acrylonitrile or propenenitrile, has been detected first toward Sgr B2:\\		Vinyl cyanide, C<sub>2</sub>H<sub>3</sub>CN, aka acrylonitrile or propenenitrile, has been detected first toward Sgr B2:\\
	F. F. Gardner and G. Winnewisser,\\		F. F. Gardner and G. Winnewisser,\\
-	[[http://cdsads.u-strasbg.fr/abs/1975ApJ...195L.127G\|The Detection of Interstellar Vinyl Cyanide (Acrylonitrile)]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1975ApJ...195L.127G\|The Detection of Interstellar Vinyl Cyanide (Acrylonitrile)]],\\
	//Astrophys. J.// 195, L127–L130 (1975).		//Astrophys. J.// 195, L127–L130 (1975).

	The molecule was also detected in the dark cloud TMC-1:\\		The molecule was also detected in the dark cloud TMC-1:\\
	H.E. Matthews and T.J. Sears,\\		H.E. Matthews and T.J. Sears,\\
-	[[http://adsabs.harvard.edu/abs/1983ApJ...272..149M\|The Detection of Vinyl Cyanide in TMC-1]],\\	+	[[https://ui.adsabs.harvard.edu/abs/1983ApJ...272..149M\|The Detection of Vinyl Cyanide in TMC-1]],\\
	//Astrophys. J.// 272, 149–153 (1983).		//Astrophys. J.// 272, 149–153 (1983).

	It was seen also in one of three translucent clouds (CB 17):\\		It was seen also in one of three translucent clouds (CB 17):\\
	B. E. Turner, R. Terzieva, and E. Herbst,\\		B. E. Turner, R. Terzieva, and E. Herbst,\\
-	[[http://dx.doi.org/10.1086/307300\|The Physics and Chemistry of Small Translucent Molecular Clouds. XII. More Complex Species Explainable by Gas-Phase Processes]]\\	+	[[https://doi.org/10.1086/307300\|The Physics and Chemistry of Small Translucent Molecular Clouds. XII. More Complex Species Explainable by Gas-Phase Processes]]\\
	//Astrophys. J.// 518, 699–732 (1999).		//Astrophys. J.// 518, 699–732 (1999).

	Quite recently, C<sub>2</sub>H<sub>3</sub>CN was among several molecules detected with the IRAM 30 m telecope in the circumstellar envelope of the carbon-rich AGB star CW Leo, aka IRC +10216:\\		Quite recently, C<sub>2</sub>H<sub>3</sub>CN was among several molecules detected with the IRAM 30 m telecope in the circumstellar envelope of the carbon-rich AGB star CW Leo, aka IRC +10216:\\
	M. Agúndez, J. P. Fonfría Expósito, J. Cernicharo, J. R. Pardo and M. Guélin,\\		M. Agúndez, J. P. Fonfría Expósito, J. Cernicharo, J. R. Pardo and M. Guélin,\\
-	[[http://dx.doi.org/10.1051/0004-6361:20078956\|Detection of Circumstellar CH<sub>2</sub>CHCN, CH<sub>2</sub>CN, CH<sub>3</sub>CCH, and H<sub>2</sub>CS]]\\	+	[[https://doi.org/10.1051/0004-6361:20078956\|Detection of Circumstellar CH<sub>2</sub>CHCN, CH<sub>2</sub>CN, CH<sub>3</sub>CCH, and H<sub>2</sub>CS]]\\
	//Astron. Astrophys.// 479, 493–501 (2008).		//Astron. Astrophys.// 479, 493–501 (2008).

	Vinyl cyanide in its two lowest vibrational states //v//<sub>11</sub> = 1 (in plane CCN bend; 239 cm<sup>–1</sup>) and //v//<sub>15</sub> = 1 (out of plane CCN bend; 340 cm<sup>–1</sup>) has been detected toward Sgr B2(N):\\		Vinyl cyanide in its two lowest vibrational states //v//<sub>11</sub> = 1 (in plane CCN bend; 239 cm<sup>–1</sup>) and //v//<sub>15</sub> = 1 (out of plane CCN bend; 340 cm<sup>–1</sup>) has been detected toward Sgr B2(N):\\
	A. Nummelin, P. Bergman,\\		A. Nummelin, P. Bergman,\\
-	[[http://cdsads.u-strasbg.fr/abs/1999A%26A...341L..59N\|Vibrationally Excited Vinyl Cyanide in Sgr B2(N)]]\\	+	[[https://ui.adsabs.harvard.edu/abs/1999A%26A...341L..59N\|Vibrationally Excited Vinyl Cyanide in Sgr B2(N)]]\\
	//Astron. Astrophys.// 341, L59–L62 (1999).\\		//Astron. Astrophys.// 341, L59–L62 (1999).\\
	Previously, three and two lines, respectively, detected in an Orion KL survey have been assigned to vinyl cyanide in its //v//<sub>11</sub> = 1 and //v//<sub>15</sub> = 1 states:\\		Previously, three and two lines, respectively, detected in an Orion KL survey have been assigned to vinyl cyanide in its //v//<sub>11</sub> = 1 and //v//<sub>15</sub> = 1 states:\\
	P. Schilke, T. D. Groesbeck, G. A. Blake, and T. G. Phillips,\\		P. Schilke, T. D. Groesbeck, G. A. Blake, and T. G. Phillips,\\
-	[[http://dx.doi.org/10.1086/312948\|A Line Survey of Orion KL from 325 to 360 GHz]],\\	+	[[https://doi.org/10.1086/312948\|A Line Survey of Orion KL from 325 to 360 GHz]],\\
	//Astrophys. J. Suppl. Ser.// 108, 301–337 (1997).		//Astrophys. J. Suppl. Ser.// 108, 301–337 (1997).

	Observations of <sup>13</sup>C singly substituted species in Sgr B2(N) have been reported:\\		Observations of <sup>13</sup>C singly substituted species in Sgr B2(N) have been reported:\\
	H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, and P. Schilke,\\		H. S. P. Müller, A. Belloche, K. M. Menten, C. Comito, and P. Schilke,\\
-	[[http://dx.doi.org/10.1016/j.jms.2008.03.016\|Rotational Spectroscopy of Isotopic Vinyl Cyanide, H<sub>2</sub>C=CH–C≡N, in the Laboratory and in Space]],\\	+	[[https://doi.org/10.1016/j.jms.2008.03.016\|Rotational Spectroscopy of Isotopic Vinyl Cyanide, H<sub>2</sub>C=CH–C≡N, in the Laboratory and in Space]],\\
	//J. Mol. Spectrosc.// 250, 319–325 (2008).\\		//J. Mol. Spectrosc.// 250, 319–325 (2008).\\
	The astronomical observations are based on a molecular line survey carried out with the IRAM 30 m telescope at 3 mm with additional measurements at 2 and 1.3 mm.		The astronomical observations are based on a molecular line survey carried out with the IRAM 30 m telescope at 3 mm with additional measurements at 2 and 1.3 mm.
Line 38:		Line 38:
	The molecular line survey, mentioned in the previous paragraph, was described in detail by\\		The molecular line survey, mentioned in the previous paragraph, was described in detail by\\
	A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\		A. Belloche, H. S. P. Müller, K. M. Menten, P. Schilke, and C. Comito:\\
-	[[http://dx.doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\	+	[[https://doi.org/10.1051/0004-6361/201321096\|Complex Organic Molecules in the Interstellar Medium: IRAM 30 m Line Survey of Sagittarius B2(N) and (M)]]\\
	//Astron. Astrophys.// 559, Art. No. A47 (2013).\\		//Astron. Astrophys.// 559, Art. No. A47 (2013).\\
	A total of six excited vibrational states of vinyl cyanide were observed in this work. They are //v//<sub>11</sub> = 1, //v//<sub>15</sub> = 1, which both were seen before, plus newly //v//<sub>11</sub> = 2, //v//<sub>11</sub> = //v//<sub>15</sub> = 1, //v//<sub>11</sub> = 3, and //v//<sub>11</sub> = 3. The latter state has a vibrational energy of about 688 cm<sup>–1</sup> or about 990 K.		A total of six excited vibrational states of vinyl cyanide were observed in this work. They are //v//<sub>11</sub> = 1, //v//<sub>15</sub> = 1, which both were seen before, plus newly //v//<sub>11</sub> = 2, //v//<sub>11</sub> = //v//<sub>15</sub> = 1, //v//<sub>11</sub> = 3, and //v//<sub>11</sub> = 3. The latter state has a vibrational energy of about 688 cm<sup>–1</sup> or about 990 K.
Line 44:		Line 44:
	A. López, B. Tercero, Z. Kisiel, A. M. Daly, C. Bermúdez, H. Calcutt, N. Marcelino, S. Viti, B.J. Drouin, I. R. Medvedev, C. F. Neese, L. Pszczólkowski, J. L. Alonso, and J. Cernicharo\\		A. López, B. Tercero, Z. Kisiel, A. M. Daly, C. Bermúdez, H. Calcutt, N. Marcelino, S. Viti, B.J. Drouin, I. R. Medvedev, C. F. Neese, L. Pszczólkowski, J. L. Alonso, and J. Cernicharo\\
	reported on\\		reported on\\
-	[[http://dx.doi.org/10.1051/0004-6361/201423622\|Laboratory Characterization and Astrophysical Detection of Vibrationally Excited States of Vinyl Cyanide in Orion-KL]]\\	+	[[https://doi.org/10.1051/0004-6361/201423622\|Laboratory Characterization and Astrophysical Detection of Vibrationally Excited States of Vinyl Cyanide in Orion-KL]]\\
	//Astron. Astrophys.// 572, (2014), Art. No. A44.\\		//Astron. Astrophys.// 572, (2014), Art. No. A44.\\
	The authors detect one further state newly, //v//<sub>10</sub> = 1, which interacts strongly with //v//<sub>11</sub> = //v//<sub>15</sub> = 1.		The authors detect one further state newly, //v//<sub>10</sub> = 1, which interacts strongly with //v//<sub>11</sub> = //v//<sub>15</sub> = 1.
Line 52:		Line 52:

	Contributor(s): H. S. P. Müller, 12, 2003; 06, 2008; 03, 2012; 11, 2014		Contributor(s): H. S. P. Müller, 12, 2003; 06, 2008; 03, 2012; 11, 2014
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