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arXiv · 1301.1830

The Effect of an Inert Solid Reservoir on Molecular Abundances in Dense Interstellar Clouds

Juris Kalvans·Ivar Shmeld
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Abstract

The question, what is the role of freeze-out of chemical species in determining the molecular abundances in the interstellar gas is a matter of debate. We investigate a theoretical case of a dense interstellar molecular cloud core by time-dependent modelling of chemical kinetics, where grain surface reactions deliberately are not included. That means, the gas-phase and solid-phase abundances are influenced by gas reactions, accretion on grains, and desorption, only. We compare the results to a reference model, where no accretion occurs and only gas-phase reactions are included. We can trace that the purely physical processes of molecule accretion and desorption have major chemical consequences on the gas-phase chemistry. The main effect of introduction of the gas-grain interaction is long-term molecule abundance changes that come nowhere near an equilibrium in during the typical lifetime of a prestellar core.

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Juris Kalvans, Ivar Shmeld. 2013-01-09. The Effect of an Inert Solid Reservoir on Molecular Abundances in Dense Interstellar Clouds. https://doi.org/10.1515/astro-2017-0402

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