Role of coulomb deflection in light ion induced L shell ionization

Abstract

Measured L subshell ionization cross sections for H + and He + bombardment of Sb ( Z = 51), Gd ( Z = 64), W ( Z = 74) and Au ( Z = 79) targets in the energy range 0.1–2.0 MeV u are compared with the ECPSSR theory. Significant discrepancies between experiment and theory are observed for the L 2, subshell and for bombarding ion energies below about 0.5 MeV u . Since binding (PSS) and relativistic (R) effects have similar but opposite effects on the L subshell ionization cross sections the differences are examined in terms of the Coulomb deflection (C) of the bombarding particle. For the L 2 subshell at least, the Coulomb deflection factors incorporated in the ECPSSR theory overestimate the reduction in the ionization cross sections by a factor of ~ 2 for bombarding ion energies below about 0.5 MeV u .