The Theoretical Cross Section forKElectron Ionization by Electron Impact

Abstract

Born's approximation is applied to the general problem of single $K$ shell ionization without excitation. Slater's wave functions are used and a formula is derived which expresses the cross section as a function of the atomic number, the ionization potential of the $K$ shell and the energy of the colliding electron. By comparison with experimental measurements the theory is shown to give good qualitative results for collision energies above about three times the ionization energy.