J. Cernicharo, C. Cabezas, Y. Endo, M. Agúndez, B. Tercero, J. R. Pardo, N. Marcelino, and P. de Vicente
report on
The Sulphur Saga in TMC-1: Discovery of HCSCN and HCSCCH
Astron. Astrophys. 650, Art. No. L14 (2021).
HC₂CHS was identified through 6 a-type transitions, of which 5 appear to be unblended, with 5 ≤ J ≤ 8 and K_a ≤ 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_rot = 5.0 K was assumed, in keeping with cyanothioformaldehyde. The column density of HC₂CHS is about a factor of 5 lower than that of the isovalent HC₂CHO, similar to the corresponding factor of 10 between thioformaldehyde and formaldehyde. In addition, the column density of HC₂CHS is about a factor of 4 lower than that of the isoelectronic HC(S)CN; the latter molecule is unusually abundant in TMC-1.

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