Partial ionization cross-sections of rubidium atom by electron impact

Abstract

The partial ionization cross-sections of the 5s, 4p⁶, 4s², 3d¹⁰ shells of a rubidium atom are calculated by using the relativistic distorted-wave, Coulomb-Born and binary–encounter–dipole approximations for the incident electron energies from the threshold up to 600 eV. The comparative analysis of the data with the experimental autoionization cross-section and the total single ionization cross-section of a rubidium atom is performed. Each of the considered approximations reflects satisfactorily the direct ionization of rubidium atom only in the certain energy regions, namely, the distorted-wave approximation at low impact energies, and the binary–encounter–dipole approximation at high impact energies.