The use of some further simplifications in the usual impulse-approximation scheme provides a simple computational method for the evaluation of ejected-electron cross sections. Except for very low energies of incoming and ejected electrons, our treatment also exhibits the usefulness of Compton profiles for the description of ejected electrons. As an illustration, the case of helium has been investigated here. The proposed treatment appears to give a standard representation for the comparison of a whole set of previous experimental and theoretical results.

• Received 19 June 1981

DOI:https://doi.org/10.1103/PhysRevA.25.1768