Authors: Cernicharo, J.; Cabezas, C.; Agundez, M.; Tercero, B.; Pardo, J. R.; Marcelino, N.; Gallego, J. D.; Tercero, F.; Lopez-Perez, J. A.; de Vicente, P.
Journal: ASTRONOMY & ASTROPHYSICS
Publication date: 2021/04/07
Abstract: We report the detection of the sulfur-bearing species NCS, HCCS, H2CCS, H2CCCS, and C4S for the first time in space. These molecules were found towards TMC-1 through the observation of several lines for each species. We also report the detection of C5S for the first time in a cold cloud through the observation of five lines in the 31-50 GHz range. The derived column densities are N(NCS) = (7.8 +/- 0.6) x 10(11) cm(-2), N(HCCS) = (6.8 +/- 0.6) x 10(11) cm(-2), N(H2CCS) = (7.8 +/- 0.8) x 10(11) cm(-2), N(H2CCCS) = (3.7 +/- 0.4) x 10(11) cm(-2), N(C4S) = (3.8 +/- 0.4) x 10(10) cm(-2), and N(C5S) = (5.0 +/- 1.0) x 10(10) cm(-2). The observed abundance ratio between C3S and C4S is 340, that is to say a factor of approximately one hundred larger than the corresponding value for CCS and C3S. The observational results are compared with a state-of-the-art chemical model, which is only partially successful in reproducing the observed abundances. These detections underline the need to improve chemical networks dealing with S-bearing species.