Effects of configuration and parentage mixing on inner-shell excitation of highly charged lithiumlike ions by electron impact

Abstract

Electron-impact scaled collision strengths $Z^2\Omega$ for a large number of inner-shell excitation transitions involving configuration-mixed and/or parentage-mixed upper levels are obtained for lithiumlike ions in the limit $Z\to \infty$. Since this is the simplest case for which both parentage and configuration mixing occur, this problem is of intrinsic interest to the atomic physicist. The results are also expected to be of interest in applications to highly charged lithiumlike ions occurring in high-temperature, low-density plasmas. The effects of mixing are found to be large in several cases. However, as for the unmixed results, the collision strengths can still be expressed in a simple way in terms of the scaled hydrogenic ion collision strengths $Z^2{\Omega }_{\mathrm{H}}$ and $Z^2{\Omega }_{\mathrm{H}}^e$.