ABSTRACT
The disturbance of a gaseous medium by a source of high energy electrons causes the formation of the strong nonequilibrium distribution of secondary electrons on their kinetic energies. A more general treatment of the electron degradation spectrum and determination of excitation and ionization rates are based on an analysis of the Boltzmann kinetic equation for the electron energy distribution function. It is known that the form of the electron degradation spectrum in the range of threshold energies is practically independent of the primary source electron distribution if the energy of source electrons exceeds the value about 300 eV. The electron-molecule frequencies are proportional to appropriate molecule concentrations. The analytical approximations obtained may be useful especially in connection with the analytical formulas for a space distribution of the energy transferred to a gas by high energy electrons.
