Hot hydrogen and deuterium in the exosphere of Venus

A theoretical study of the production, thermalization and escape, of hot atomic hydrogen and deuterium in the exosphere of Venus is presented. The approach adopted involves the quantum mechanical calculation of the charge exchange collision cross sections for (H⁺, H) and (D+, H) collisions, the production of translationally energetic atoms, and their ensuing thermalization and escape from Venus. A kinetic theory which employs the quantum mechanical collision cross sections and accounts for the production, thermalization and escape of hot atoms is described. Preliminary numerical results for escape fluxes calculated with density and temperature profiles as provided from the Pioneer Venus orbiter are presented.