===== On the Detection of Thiosulfeno, HS2, in Space =====

A. Fuente, J. R. Goicoechea, J. Pety, R. Le Gal, R. Martín-Doménech, P. Gratier, V. Guzmán, E. Roueff, J. C. Loison, G. M. Muñoz Caro, V. Wakelam, M. Gerin, P. Riviere-Marichalar, and T. Vidal,\\
reported on the\\
**[[https://doi.org/10.3847/2041-8213/aaa01b|First Detection of Interstellar S<sub>2</sub>H]]**,\\
//Astrophys. J.// **851** L49 (2017).\\
The 6<sub>0,6</sub> – 5<sub>0,5</sub> and 7<sub>0,7</sub> – 6<sub>0,6</sub> transitions near 94.6 and 110.4 GHz were detected with the IRAM 30 m telescope in emission toward the Horsehead photodissociation region. The large fine structure splitting was resolved, the very small HFS splitting was not resolved. The radical occurs widespread in this source, both in the interface region (HCO peak) and in the denser and colder region (DCO<sup>+</sup> peak). Its column density is only a factor of about four to six lower in this source than that of H<sub>2</sub>S.\\
\\

More recently,  G. Esplugues, M. Agúndez, G. Molpeceres, B. Tercero, C. Cabezas, N. Marcelino, R. Fuentetaja, and J. Cernicharo\\
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.\\
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Contributor(s): H. S. P. Müller; 12, 2017; 07, 2025

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