Paper VIII

Electron-excitation of the 3d$^4$ 5D$_j$ ground-state fine-structure transitions

in Ti-like ions V-II, Cr-III, Mn-IV, Fe-V, Co-VI and Ni-VII

Berrington.KA

Astronomy & Astrophysics Supplement Series, 1995, Vol.109, No.1, pp.193-197

Electron excitation collision strengths for the 3d$^4$ $^5$D $_{\mbox{J-J'}}$ ground term fine-structure transitions in titanium-like ions V II, Cr III, Mn IV, Fe V, Co VI and Ni VII are calculated using R-matrix techniques. The model target ion includes all 3d$^4$ terms, and the low-energy collision strengths are dominated by autoionizing resonances. The collision strength is averaged over a Maxwellian velocity distribution to obtain effective collision strengths as a function of electron temperature. To our knowledge, these are the first published data for these processes.