Fine structure collision strengths for S VII lines

Abstract

Energy levels, oscillator strengths, radiative decay rates and fine structure collision strengths are presented for six times ionized sulfur S VII. The atomic data are calculated with the SUPERSTRUCTURE code, where relativistic corrections are introduced according to the Breit–Pauli approach. We include in this work the (1s2) 2s22p6, 2s22p53l, 2s2p63l, 2s22p54l (l ⩽ n − 1) configurations that yield the lowest 75 levels. The scattering problem is treated in the distorted wave approach by the code DISTORTED WAVE. This produces collision strengths in LS coupling that will be used by the code JAJOM to transform them into fine structure ones. Fine structure collision strengths for transitions from the ground and the first four excited levels are presented at six electron energies from 20 to 120 Ryd by a step of 20 Ryd. Our atomic structure data are compared with the available experimental and theoretical results.