Analogues of relativistic integrals: their application in R-matrix method for highly charged tungsten ions

Abstract

The electron-impact collision strength calculations using different R-matrix code versions are performed for the 1s²2s²2p⁶3s²3p⁶3d¹⁰4l (l = 0, 1, 2, 3) configuration levels of the W⁴⁵⁺ ion. The influence of relativistic effects on the bound-bound, bound-continuum, and continuum-continuum integrals of the collision strength is studied in quasirelativistic and relativistic approximations. A suitability of our introduced relativistic integrals method for highly charged ions is cross-checked by comparing results of different relativistic calculation methods.