Open AccessEscape of H and D from Mars and Venus by energization with hot oxygen
Author(s) -
Shizgal Bernie D.
Publication year - 1999
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/1999ja900157
Subject(s) - venus , mars exploration program , dissociative recombination , atmospheric escape , atomic physics , physics , oxygen , kinetic energy , atmosphere of venus , atmosphere of mars , hot atom , astrobiology , chemistry , recombination , martian , classical mechanics , biochemistry , quantum mechanics , gene
A kinetic theory collisional production model is used to determine the product velocity distributions of H and D resulting from collisional energy transfer with hot oxygen. The energetic oxygen atoms are the products of the dissociative recombination of O 2 + . Quantum mechanical cross sections for O‐H and O‐D collisions are used to determine the production distributions. The distributions of the particles entering a collision are assumed to be Maxwellian functions. The fraction of atoms with speeds above the escape speed is determined for Venus and Mars. For Venus, available density and temperature profiles are used to obtain estimates of the H and D escape fluxes and fractionation ratios.