A UNIFIED MONTE CARLO TREATMENT OF GAS-GRAIN CHEMISTRY FOR LARGE REACTION NETWORKS. I. TESTING VALIDITY OF RATE EQUATIONS IN MOLECULAR CLOUDS

@article{Vasyunin2009AUM,
  title={A UNIFIED MONTE CARLO TREATMENT OF GAS-GRAIN CHEMISTRY FOR LARGE REACTION NETWORKS. I. TESTING VALIDITY OF RATE EQUATIONS IN MOLECULAR CLOUDS},
  author={Anton I. Vasyunin and Dimitri Semenov and Dmitri Wiebe and The Inter-University Centre for Astronomy and Heidelberg and H Germany and Institute of Astronomy Ras and Moscow and Russia.},
  journal={The Astrophysical Journal},
  year={2009},
  volume={691},
  pages={1459-1469}
}
In this study, we demonstrate for the first time that the unified Monte Carlo (MC) approach can be applied to model gas-grain chemistry in large reaction networks. Specifically, we build a time-dependent gas-grain chemical model of the interstellar medium, involving about 6000 gas-phase and 200 grain-surface reactions. This model is used to test the validity of the standard and modified rate equation methods in models of dense and translucent molecular clouds and to specify under which… Expand

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