Oxygen fractionation in dense molecular clouds.
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ABSTRACT:
SUBMITTER: Loison JC
PROVIDER: S-EPMC6699989 | biostudies-literature | 2019 Jun
REPOSITORIES: biostudies-literature
Publications
Oxygen fractionation in dense molecular clouds.
Loison Jean-Christophe JC Wakelam Valentine V Gratier Pierre P Hickson Kevin M KM Bacmann Aurore A Agùndez Marcelino M Marcelino Nuria N Cernicharo José J Guzman Viviana V Gerin Maryvonne M Goicoechea Javier R JR Roueff Evelyne E Le Petit Franck F Pety Jérome J Fuente Asunción A Riviere-Marichalar Pablo P
Monthly notices of the Royal Astronomical Society 20190227 4
We have developed the first gas-grain chemical model for oxygen fractionation (also including sulphur fractionation) in dense molecular clouds, demonstrating that gas-phase chemistry generates variable oxygen fractionation levels, with a particularly strong effect for NO, SO, O<sub>2</sub>, and SO<sub>2</sub>. This large effect is due to the efficiency of the neutral <sup>18</sup>O + NO, <sup>18</sup>O + SO, and <sup>18</sup>O + O<sub>2</sub> exchange reactions. The modeling results were compare ...[more]
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