===== 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).


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Contributor(s): H. S. P. Müller; 07, 2011

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