Atomic data from the IRON Project XLI. Electron excitation rates among the3d(2) fine-structure levels of Ca-like FeVII

Electron excitation collision strengths of 3d(2) fine-structure transitions in Ca-like Fe VII are calculated using an R-matrix method, which included the 80 terms arising from the 3d(2), 3d4s, 3d4p, 3d4d, 3d4f and 3p(5)3d(3) configurations. Extensive autoionizing resonance structures together with c hannel coupling is therefore explicitly included; relativistic effects are accounted for by a term-coupling transformation. A thermal average is taken to obtain the effective fine-structure collision strength as a function of electron temperature T, for log T(K) = 4.3-6. Open 3p-shell resonances are seen to considerably enhance the background collision strength, by several factors for some of the 3d(j-->j')(2), transitions.