Recent Results on K-Shell Ionization by Ion Collisions
The experimental K-shell ionization cross sections of 48Cd, 50Sn, 52Te, 53I and 56Ba for alpha particles, between 2.2 MeV and 2.8 MeV, and of 52Te for protons, between 1.6 and 3 MeV, are presented. The justification for making these measurements comes, on the one hand, in filling a region where, at present, data are sparse: for example, 52Te ionization cross sections by alpha particles have never been reported before, and, on the other hand, checking between previously reported and diverging sets of experimental results: for example, for alpha particles on tin. In addition, the K-shell ionization cross sections of 52Te for protons can be considered as an extension of Khelill's measurements.
Relativistic corrections to the binary encounter approximation for ionisation of atoms by collisions with ions
Relativistic wavefunctions for K-shell electrons have been introduced in the binary encounter approximation for atomic ionisation together with an approximate relativistic correction of the collision dynamics. A comparison with experiment is given.
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.