Wave-function effects in the formation of 2S, 2P− and 2P+ states in collisions of lithium-like O5+ ions with He target

Abstract

Cross section calculations have been performed within the framework of the semiclassical approximation for the formation of the 1s2s22S, 1s2s2p 2P+ and 1s2s2p 2P− singly excited states of the lithium-like O5+ ion in collisions with He target. Impact parameter dependent probabilities were calculated, by taking into account the screening effect of the target electrons. We have found strong wave-function effects. Calculations using Hartree–Fock–Slater wave functions show a good general agreement with the earlier experimental data, while with screened hydrogenic wave functions the calculated cross sections were far too large for the 2P states. These results indicate that the 1s–2p excitation process is rather sensitive to electron–electron interactions in the bound states of highly charged few electron ions.