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 Title: COSMIC RAY-DRIVEN RADIATION CHEMISTRY IN COLD INTERSTELLAR ENVIRONMENTS Author(s): Shingledecker, Christopher N. Contributor(s): Herbst, Eric; Le Gal, Romane; Tennis, Jessica D. Subject(s): Astronomy Abstract: The physiochemical impact of cosmic rays on interstellar regions is widely known to be significant \footnote{Indriolo, N. \& McCall, B. J.,\textit{Chem. Soc. Rev.}, 42, 7763-7773, 2013}. Indeed, the cosmic ray-driven formation of H$_3^+$ via the ionization of H$_2$ was shown to be of key importance in even the first astrochemical models \footnote{Herbst, E. \& Klemperer, W., \textit{Ap.J.}, 185, 505-534, 1973}. Later, cosmic rays were implicated in the collisional excitation of H$_2$, which leads to the production of internally produced UV photons that also have profound effects on the chemistry of molecular clouds \footnote{Prasad, S. S. \& Tarafdar, S. P.,\textit{Ap.J.}, 267, 603-609, 1983}. Despite these key findings, though, attempts at a more complete consideration of interstellar radiation chemistry have been stymied by the lack of a general method suitable for use in astrochemical models and capable of preserving the salient macroscopic phenomena that emerge from a large number of discrete microscopic events. Recently, we have developed a theoretical framework which meets these criteria and allows for the estimation of the decomposition pathways, yields, and rate coefficients of radiation-chemical reactions \footnote{Shingledecker, C. N. \& Herbst, E., \textit{Phys. Chem. Chem. Phys.}, 20, 5359-5367, 2018}. In this talk, we present preliminary results illustrating the effect of solid-phase radiation chemistry on models of TMC-1 in which we consider the radiolysis of the primary ice-mantle constituents of dust grains. We further discuss how the inclusion of this non-thermal chemistry can lead to the formation of complex organic molecules from simpler ice-mantle constituents, even under cold core conditions. Issue Date: 06/20/18 Publisher: International Symposium on Molecular Spectroscopy Citation Info: APS Genre: Conference Paper / Presentation Type: Text Language: English URI: http://hdl.handle.net/2142/100827 DOI: 10.15278/isms.2018.WL04 Other Identifier(s): WL04 Date Available in IDEALS: 2018-08-172018-12-12
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