On our ability to measure the singly ionised rare-gas spectroscopic factors using the (γ,e) and (e,2e) reactions

Abstract

The differences between the spectroscopic factors of singly ionised rare-gas atoms (Ar, Kr, Xe) measured in photoelectron spectroscopy (the ( gamma ,e) reaction) and high-energy electron inelastic scattering (the non-coplanar symmetric (e,2e) reaction) are explained. It is shown that due to atomic ground-state many-electron correlations the ( gamma ,e) reaction gives spectroscopic factors with systematic error. On the contrary, if the momentum transfer to the ion in the ionising collision is small the (e,2e) reaction gives the correct spectroscopic factors. Comparison of the calculated and experimental ArII²S ion spectroscopic factors confirms these conclusions.