Show pageOld revisionsBacklinksBack to top This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong. ===== 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 ---- molecules/ism/hoco-plus.txt Last modified: 2019/10/22 16:42by mueller