Scaled electron ionization cross sections in the Born approximation

Abstract

The results of extensive calculations on cross sections for electron ionization of atomic subshells are presented in a scaled form. In general, the scaling is nonclassical, i.e., does not vary inversely with the square of the ionization potential. Comparison is made of the scaled $2p$ ionization cross section with measurements on Ar and Au, and good agreement is found. Comparison is made with measurements on cross sections for electron ionization of positive ions. The conclusion reached is that for ions with outer shells of low ionization potential, the scaled atomic cross sections are inaccurate, and that for such ions the cross sections are better described by the classical scaling law.