Two-electron-group model and Boltzmann calculations for low-pressure gas discharges

For Ne, Ar, and Cs-Ar positive column plasmas a comparison is presented between Boltzmann and two-electron-group model (2-EGM) calculations. This 2-EGM is an approximation method to account for deviations from a Maxwellian electron energy distribution in plasma modeling. The comparison makes it possible to obtain in the 2-EGM an accurate normalization function for the high-energy tail of the electron energy distribution. The 2-EGM is found to give electron impact collision and energy transfer rates that agree well with those from the Boltzmann calculation over a wide range of currents and pressures.