Efficiency of Molecular Hydrogen Formation on Silicates

نویسندگان

  • Valerio Pirronello
  • Ofer Biham
  • Chi Liu
  • Lyiong Shen
  • Gianfranco Vidali
چکیده

We report on laboratory measurements of molecular hydrogen formation and recombination on an olivine slab as a function of surface temperature under conditions relevant to those encountered in the interstellar medium. On the basis of our experimental evidence, we recognize that there are two main regimes of H coverage that are of astrophysical importance; for each of them we provide an expression giving the production rate of molecular hydrogen in interstellar clouds. Subject headings: dust— ISM; abundances — ISM; molecules — molecular processes

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تاریخ انتشار 1997