C. Cabezas, M. Agúndez, R. Fuentetaja, Y. Endo, N. Marcelino, B. Tercero, J. R. Pardo, P. de Vicente, and J. Cernicharo
reported on the
Discovery of the Cyclic C₅H Radical in TMC-1
Astron Astrophys. 663, Art. No. L2 (2022).
Transitions with J“ = 4 to 6 and K_a = 1 between 33.0 and 46.4 GHz were detected 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. Fine structure splitting was resolved throughout, hyperfine splitting in many cases. The C₃S to HC₃S⁺ ratio is 65 ± 20, and the HC₃O⁺ to HC₃S⁺ ratio is 1.0 ± 0.5. The C₃O to C₃S ratio, in contrast, is ~0.11.

Contributor(s): H. S. P. Müller 07, 2022