Ionization of molecular hydrogen and stripping of oxygen atoms and ions in collisions of Oq++H2 (q=0-8): Data for secondary electron production from ion precipitation at Jupiter

Energetic oxygen and sulfur ion precipitation into the atmosphere of Jupiter is thought to produce an X-ray aurora as well as to contribute to ionization, heating, and dissociation of the molecules of the atmosphere. At high energy, stripping of electrons from these ions by atmospheric gas molecules results in the production of high charge states throughout a portion of this passage through the atmosphere. Therefore, to enable modeling of the effects of secondary electrons produced by this ion precipitation, from either the solar wind or magnetospheric sources such as the Galilean moons, a large range of ionization and stripping data is calculated and tabulated here that otherwise is not available. The present data are for the abundant precipitating species, oxygen, colliding with the dominant upper atmosphere gas, molecular hydrogen, and cover the principal reaction channels leading to secondary electron production (single and double ionization, transfer ionization, and double capture followed by autoionization, and single and double stripping of electrons from the projectile). Since the ions possess initial energies at the upper atmosphere in the keV to MeV range, and are then slowed as they pass through the atmosphere, results are calculated for 1-2000 keV/u Oq++H2 (q=0-8). In addition to the total cross sections for ionization and stripping processes, models require the distribution in energy and angle of the ejected electrons, so cross sections differential in these parameters are also calculated. The data may be used to model the energy deposited by ion precipitation in Jupiter's atmosphere and thereby contribute to the elucidation of the ionosphere-atmosphere coupling.