Electron energy distribution in CO and He-CO discharges. I

Abstract

The electron energy distribution function in the positive column of CO and He-CO discharges is derived from the Boltzmann equation. Analytic expressions are given for the distribution function in different energy ranges. The coefficients in these solutions are calculated using the condition that the distribution function and its derivative are continuous. The calculations are made for different He-CO mixtures and different values of E/N, neglecting superelastic collisions. The results are approximately the same as those obtained by numerical methods. It is shown that in the energy range where vibrational excitation is the dominant process, there are conditions under which the two-term expansion of the distribution function in spherical harmonics is not valid.