The study of the energy differential cross sections of electron impact ionization for ions

Abstract

The energy differential cross sections (energy distribution of secondary electrons) of electron impact ionization for helium-like ions have been calculated by using a distorted-wave Born exchange (DBE) approximation. The authors found that the dependence of the differential cross sections on the reduced energies of secondary electron can be very well fitted with the two-parameter Gaussian function for the first time. The dependence of two parameters on the incident electron energy and target ions have been given. Also the differences between two sets of parameters from DBE and CBE (Coulomb Born exchange) approximation have been discussed.