Abstract
The free-fall atomic model has been used to describe ejection of electrons from atoms by protons. Cross sections differential with respect to angle and energy of the ejected electrons were within the BE approximation derived. It has been found that the interaction of the recoiled electron leaving the atom with the Coulomb field of the parent nucleus strongly influences the BE angular distribution, and is responsible for the observed backward ejection of electrons. Theoretical results of BE calculations corrected for the 'post-collision' deflection of recoiled electrons, that have been carried out for helium, were found to be in good agreement with the experimental data.