Electron spectra from singlet and triplet states of produced by low-energy , Ne and Ar collisions

Ejected electrons from the singlet and triplet states of doubly excited and ions, produced by 25, 50, 75 and 100 keV and Ar collisions have been measured with high-resolution electron spectroscopy. Only singlet states were observed when the target was He; in contrast, many triplet states were observed in and Ar collisions. Both singlet and triplet states contributed to the electron spectra in collisions, in particular, triplet states were conspicuous at low energy. Two theoretical methods, perturbation theory or Z expansion (MZ code) and multiconfigurational Hartree-Fock (Cowan code) were used for identification of ejected-electron spectra. The collision energy dependence of the spectra is discussed.