Photodesorption of H2O, HDO, and D2O ice and its impact on fractionation

  title={Photodesorption of H2O, HDO, and D2O ice and its impact on fractionation},
  author={Carina Arasa and Jesper Koning and G J Kroes and Catherine Walsh and Ewine F. van Dishoeck Gorlaeus Laboratories and Leiden Institute of Chemistry and Leiden University and P. O. Box 9502 and 2300 RA Leiden and The Netherlands. and Leiden Observatory and P. O. Box 9513 and Max Planck Institute for Extraterrestrial Physics and 1 Giessenbachstrasse and 85748 Garching and H Germany},
  journal={arXiv: Astrophysics of Galaxies},
The HDO/H2O ratio in interstellar gas is often used to draw conclusions on the origin of water in star-forming regions and on Earth. In cold cores and in the outer regions of protoplanetary disks, gas-phase water comes from photodesorption of water ice. We present fitting formulae for implementation in astrochemical models using photodesorption efficiencies for all water ice isotopologues obtained using classical molecular dynamics simulations. We investigate if the gas-phase HDO/H2O ratio… 

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