Differential cross sections for electron-impact ionization of helium

In an earlier paper a general formulation of differential cross sections for electron-impact ionization of atomic systems, in the Born approximation, was presented. The present work uses this formulation, with simple correlated wave functions, to evaluate various differential cross sections for electron-impact ionization of helium. The results are compared with previous experimental and theoretical data. The favorable agreement obtained with experiment for high incident-electron energies and low ejected-electron energies in both double- and single-differential cross sections is indicative of the agreement which can be expected when the same procedure is applied to the electron-impact ionization of other atoms.