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arXiv · 1509.00336

A proposed chemical scheme for HCCO formation in cold dense clouds

V. Wakelam·J. -C. Loison·K. M. Hickson·M. Ruaud
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Abstract

The ketenyl radical (HCCO) has recently been discovered in two cold dense clouds with a non-negligible abundance of a few 1e-11 (compared to H2) (Agundez et al. 2015). 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 Lupus-1A and L486. The main formation pathway for HCCO is the OH + CCH -> HCCO + H reaction as suggested by Agundez et al. (2015) 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.

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V. Wakelam, J. -C. Loison, K. M. Hickson, M. Ruaud. 2015-09-01. A proposed chemical scheme for HCCO formation in cold dense clouds. https://doi.org/10.1093/mnrasl/slv097

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