2015MNRAS.453L..48W

The ketenyl radical (HCCO) has recently been discovered in two cold dense clouds with a non-negligible abundance of a few 10^–11 (compared to H2). Until now, no chemical network has been able to reproduce this observation. We propose here a chemical scheme that can reproduce HCCO abundances together with HCO, H2CCO and CH3CHO in the dark clouds Lupu/sA and L486. The main formation pathway for HCCO is the OH + CCH -> HCCO + H reaction as suggested by Agúndez et al. but with a much larger rate coefficient than used in current models. Since this reaction has never been studied experimentally or theoretically, this larger value is based on a comparison with other similar systems.