Electron thermalization in gases. V. Diatomic molecules H2, N2, and CO

Abstract

The method introduced by one of us (AM) for calculating the thermalization times, evolution of the effective electron temperature, and other quantities of interest in electron thermalization, is extended to the diatomic molecules H₂, N₂, and CO. Starting with a displaced pseudo‐Maxwellian distribution function for energetic electrons, the evolution of the thermalization process is studied using available cross section data for elastic and inelastic processes. Careful attention has been paid to microscopic reversibility and detailed balancing. We find that, while the major contributions to thermalization are due to rotational and vibrational excitations of the gas molecules, the contribution due to elastic collisions is not negligible. We also find that the relaxation time (obtained from the relaxation time due to inelastic and elastic processes) is a significant part of the thermalization time. The relative contributions of elastic and inelastic processes are evaluated as a function of time as well as gas temperature. Calculated results are in reasonable agreement with experimental data.