Single and double ionization of magnesium by H+ and He2+ impact

Theoretical investigations of H+ and He2+ impact single and double ionization of magnesium atoms have been performed in the binary encounter approximation. Direct double ionization cross sections have been calculated in the modified binary encounter model. Accurate expressions of sigma(Delta E) (cross section for energy transfer Delta E) and Hartree-Fock velocity distributions for the target electrons have been used throughout the calculations. Contributions to double ionization from the Auger effect following a vacancy in the 2p shell have been considered in the present work. Our H+ impact single and double ionization cross sections are in good agreement with experimental observations. The calculated He2+ impact single ionization cross sections show satisfactory agreement with experiment but in the case of double ionization, success is limited in the experimentally investigated region (42.5-438 keV amu(-1)).