R-matrix electron-impact excitation data for the Li-like iso-electronic sequence including Auger and radiation damping

Abstract

We present results for the electron-impact excitation of all Li-like ions from Be+ to Kr33+ which we obtained using the radiation- and Auger-damped intermediate-coupling frame transformation R-matrix approach. We have included both valence- and core-electron excitations up to the 1s(2)5l and 1s2l4l' levels, respectively. A detailed comparison of the target structure and collision data has been made for four specific ions (O5+, Ar15+, Fe23+ and Kr33+) spanning the sequence so as to assess the accuracy for the entire sequence. Effective collision strengths (gamma s) are presented at temperatures ranging from 2 x 10(2)(z + 1)(2) K to 2 x 10(6)(z + 1)(2) K (where z is the residual charge of the ions, i.e. Z - 3). Detailed comparisons for the gamma s are made with the results of previous calculations for several ions which span the sequence. The radiation and Auger damping effects were explored for core-excitations along the iso-electronic sequence. Furthermore, we examined the iso-electronic trends of effective collision strengths as a function of temperature.