<i>K</i>, <i>L</i>, and <i>M</i> shell generalized oscillator strengths and ionization cross sections for fast electron collisions

TLDR

The study calculates generalized oscillator strengths and ionization cross sections for K, L, and M shells via fast electron impact. The authors use a nonrelativistic Hartree–Slater program to generate initial and continuum wave functions, then compute core edge shapes and their momentum‑transfer dependence up to several hundred eV above threshold. Computed core edge shapes agree well with experiment in gross spectral shape, confirming the hydrogenic model for K edges and providing more accurate total cross sections for L and M shell excitation.

Abstract

Generalized oscillator strengths and ionization cross sections by fast electron impact are calculated for K, L, and M shells. A nonrelativistic Hartree–Slater program is used to generate the initial states as well as the continuum wave functions. Core edge shapes and their dependence on momentum transfer are computed within this atomic model up to some tens or hundreds of eV above threshold. Some comparisons are made with experimental measurements and though details near threshold are not predicted, the gross shape of the spectrum is in quite good agreement with these data. While we confirm that the hydrogenic model is a reasonable approximation for K edges, we expect our computations to be useful in obtaining more accurate total cross sections for L and M shell excitation.