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arXiv · 2401.11785

Discovery of thiofulminic acid with the QUIJOTE line survey: A study of the isomers of HNCS and HNCO in TMC-1

José Cernicharo·Marcelino Agúndez·Carlos Cabezas·Belén Tercero·Raúl Fuentetaja·Nuria Marcelino·Pablo de Vicente
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Abstract

We present the first detection of HCNS (thiofulminic acid) in space with the QUIJOTE line survey in the direction of TMC-1. We performed a complete study of the isomers of CHNS and CHNO, including NCO and NCS. The derived column densities for HCNS, HNCS, and HSCN are (9.0+/-0.5)e9, (3.2+/-0.1)e11, and (8.3+/-0.4)e11 cm-2, respectively. The HNCS/HSCN abundance ratio is 0.38. The abundance ratios HNCO/HNCS, HCNO/HCNS, HOCN/HSCN, and NCO/NCS are 34+/-4, 8.3+/-0.7, 0.18+/-0.03, and 0.78+/-0.07, respectively. These ratios cannot be correctly reproduced by our gas-phase chemical models, which suggests that formation paths for these species are missing, and/or that the adopted dissociative recombination rates for their protonated precursors have to be revised. The isotopologues H15NCO, DNCO, N13CO, DCNO, H34SCN, and DSCN have also been detected with the ultrasensitive QUIJOTE line survey.

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José Cernicharo, Marcelino Agúndez, Carlos Cabezas, Belén Tercero, Raúl Fuentetaja, Nuria Marcelino, Pablo de Vicente. 2024-01-22. Discovery of thiofulminic acid with the QUIJOTE line survey: A study of the isomers of HNCS and HNCO in TMC-1. https://doi.org/10.1051/0004-6361%2F202349105

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