K-shell ionisation cross sections for Co, Ni, Cu, Zn, Ge and Se by protons of 0.2–2 MeV

Abstract

Proton-induced K-shell ionisation cross sections for Co, Ni, Cu, Zn, Ge and Se in the incident energy range 0.2 to 2 MeV obtained from thin target measurements are presented and compared to other available experimental results and to theoretical values pertaining to the SCA and PWBA theories, calculated taking into account electron binding energy, projectile Coulomb retardation and electronic relativistic effects. Theoretical BEA cross sections, corrected for the slowing down of the projectile in the nuclear Coulomb field, are also compared to experiment. The present data show that the correction procedues used on both the SCA and BEA calculations fail to produce acceptable agreement with experiment at low bombarding energies, while those pertinent to the PWBA still need some refinement. K Δ K α ratios are also presented and compared to other experimental values and to the theoretical one-hole values given by Scofield.