Charge exchange of multiply charged fluorine and lithium ions with Ne atoms

Abstract

The charge exchange of multiply charged fluorine and lithium ions with Ne atoms in a gas jet was recorded from the line spectra in the 125 — 350 Å range, which arise from the radiative decay of the excited states of Li II — III and F III — VIII ions populated in the charge exchange. In the F III — VI ion spectra obtained from the plasma — gas interaction region we observed transitions from levels with an open (partly filled or completely open) 2s-shell, which may be populated in sequential events of single-electron charge exchange as well as in double- and many-electron charge exchange. Partial cross sections were calculated for the single-electron charge exchange of F VIII ions with Ne atoms. By way of Hartree — Fock energy level calculations it was possible to reveal resonances between the ground states of k-fold (k = 1 — 4) ionised donor atoms and the states of k-fold excited multiply charged fluorine ion resulting from the k-fold charge exchange of F VIII ions. These resonances may be responsible for the relatively large cross sections of double- and many-electron charge exchange