He+Impact Double Ionization of Noble Gases

Abstract

Theoretical calculations of He+ impact double ionization of Ne, Ar, Kr and Xe havebeen performed in the Modified Binary Encounter Approximation. Direct doubleionization cross sections have been calculated in the modified binary encountermodel. Accurate expression of ∆ (cross section for energy transfer ∆E) and Hatree-Fock velocity distributions for the target electrons have been used throughout thecalculations. The present results of double ionization cross sections are in excellentagreement with the experimental observations in the case of Ne, Ar and Krthroughout the energy range. The calculated cross sections differs from theexperimental results in the low energy regions in case of Xe because the presentapproximation not exhibits better result in the low energy regions, while the over-estimations of experimental results in the high energy regions shows that moretheoretical calculations is required to understand the dynamics of the system.KEYWORDS Hartree-Fock, Double Ionization, Cross-sections, Vriens