Proton impact L-shell ionisation of atoms

L-shell ionisation cross sections of Ar, Cu, Kr, Ag and Xe have computed using Vriens' expressions for ionisation of atoms by proton impact. The effects of Coulomb deflection of the incident proton and the increase in binding of the target electron have been investigated separately. Hartree-Fock velocity distributions for the target electrons have been used in the present calculations. The results have been compared with the available experimental results and calculations of other workers. The simple modified BEA is found to be as effective in predicting proton impact L-shell ionisation cross sections of atoms as the complicated CPSST theory. (orig.)