Electron spectra from singlet and triplet states of Ne6+**produced by low energy Ne8+ + He, Ne and Ar collisions

Abstract

Ejected electron spectra from the singlet and triplet states of doublyexcited Ne6+**(1s22pnl), Ne6+**(1s23l3l') and Ne6+**(1s23l4l') ions, produced by 80 keV Ne8+(1s2) + He, Ne and Arcollisions, have been measured by means of a zero-degree electronspectroscopy. Only singlet states were observed when the target was He.In contrast, the contribution from the triplet states prevailed in thespectra for the Ne target. For the Ar target, practically no signals wereobserved in theenergy region for the 1s23lnl' states. Two theoretical methods,theperturbation theory (MZ code) and the multi-configurational Hartree-Fock(Cowan code) were used for identification of ejected-electron spectra. Usingthe (j) string analysis in the extended classical over-barrier model, wediscuss the possibility of the participation of inner electrons in theprocess of double-electron capture by highly charged ionmulti-electron target atoms.