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arXiv · 1605.00048

Recommended Thermal Rate Coefficients for the C + H$_3^+$ Reaction and Some Astrochemical Implications

S. Vissapragada·C. F. Buzard·K. A. Miller·A. P. O'Connor·N. de Ruette·X. Urbain·D. W. Savin
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Abstract

We have incorporated our experimentally derived thermal rate coefficients for C + H$_3^+$ forming CH$^+$ and CH$_2^+$ into a commonly used astrochemical model. We find that the Arrhenius-Kooij equation typically used in chemical models does not accurately fit our data and use instead a more versatile fitting formula. At a temperature of 10 K and a density of 10$^4$ cm$^{-3}$, we find no significant differences in the predicted chemical abundances, but at higher temperatures of 50, 100, and 300 K we find up to factor of 2 changes. Additionally, we find that the relatively small error on our thermal rate coefficients, $\sim15\%$, significantly reduces the uncertainties on the predicted abundances compared to those obtained using the currently implemented Langevin rate coefficient with its estimated factor of 2 uncertainty.

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S. Vissapragada, C. F. Buzard, K. A. Miller, A. P. O'Connor, N. de Ruette, X. Urbain, D. W. Savin. 2016-09-12. Recommended Thermal Rate Coefficients for the C + H$_3^+$ Reaction and Some Astrochemical Implications. https://doi.org/10.3847/0004-637x%2F832%2F1%2F31

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