On the Semi-classical Method for Electron Scattering by Atoms

Abstract

In applications of the semi-classical approximation to excitation of atoms by electron impact, it is commonly assumed that the trajectory of the incident electron can be taken to be a straight line. The validity of this assumption is tested by comparing cross sections obtained in a coupled channel model using either a straight line trajectory or a trajectory computed from an effective potential. It is found that as far as total cross sections are concerned the assumption of a straight line trajectory does not cause appreciable error for elastic scattering at incident energies above 200 eV and for inelastic scattering above 100 eV. The influence of the choice of trajectory on the angular distributions is discussed briefly.