Inelastic collisions and velocity distribution function of electrons in a gas in an electric field

摘要: Abstract An analysis of the current procedure solution Boltzmann equation for electrons undergoing elastic, inelastic and superelastic collisions in a gas an electric field is performed. Particular attention devoted to studying conditions under which electron velocity distribution can be approximated by first two terms its expansion spherical harmonics. It shown that often this two-term approximation, although generally used, inadequate. Sometimes it must replaced three-term approximation; numerical followed such cases discussed. In other even approximation fails, new methods developed. Previous works authors are also discussed, some physical situations particular interest examined light our theory. Finally, determination electron-neutral cross sections from transport data criticized.