Semiempirical analysis of electron-inducedK-shell ionization

We report the results of an analysis of the available experimental data on electron-induced $K$-shell ionization which show that the data can be described by the Bethe theory of ionization corrected for relativistic energies by a classical correction. This analysis, which extends over five orders of magnitude in the ratio of bombarding energy to ionization potential, appears to be superior to the available theoretical treatments, and suggests where further work would be useful.