| Autor: |
Kalvāns Juris, Shmeld Ivar |
| Jazyk: |
angličtina |
| Rok vydání: |
2012 |
| Předmět: |
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| Zdroj: |
Open Astronomy, Vol 21, Iss 4, Pp 447-454 (2012) |
| Druh dokumentu: |
article |
| ISSN: |
2543-6376 |
| DOI: |
10.1515/astro-2017-0402 |
| Popis: |
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 modeling of chemical kinetics, where grain surface reactions deliberately are not included. That means, the gas-phase and solid-phase abundances are influenced only by gas reactions, accretion on grains and desorption. 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 during the typical lifetime of a prestellar core. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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