Astrochemical Bistability: Autocatalysis in Oxygen Chemistry

  title={Astrochemical Bistability: Autocatalysis in Oxygen Chemistry},
  author={Gw{\'e}na{\"e}lle Dufour and Steven B. Charnley},
  journal={arXiv: Astrophysics of Galaxies},
The origin of bistable solutions in the kinetic equations describing the chemistry of dense interstellar clouds is explained as being due to the autocatalysis and feedback of oxygen nuclei from the oxygen dimer (O2). We identify four autocatalytic processes that can operate in dense molecular clouds, driven respectively by reactions of H+, He+, C+, and S+ with O2. We show that these processes can produce the bistable solutions found in previous studies, as well as the dependence on various… Expand

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