Photoelectron excitation of the Jupiter dayglow

The photoelectron impact contribution to the Jupiter dayglow is estimated for an atmospheric model with and without helium. Primary photoelectron production rates are calculated at specific altitudes for zero solar zenith angle and a 10.7-cm flux of 150. Extensive excitation, dissociation, and ionization cross-section data for H2, He, and H are used to model the energy deposition of photoelectrons produced locally. Volume emission rates are calculated from the direct excitation rates by applying appropriate corrections for cascading and quenching. Finally, estimates are made of intensities above the atmosphere as viewed near normal incidence with multiple scattering and absorption neglected. Rather strong emissions are predicted for the Werner and Lyman bands and the triplet continuum (a³Σg+ -b³Σu+) of H2. The photoelectron impact contribution to the most intense emissions from He and H is found to be relatively small while strong resonant scattering contributions seem reasonable.