Electron-impact Ionization of Krypton Ions (q=8-13)

Abstract

Absolute cross sections for electron impact single ionization of Kr10+ and Kr11+ ions and double ionization of Kr-q+ (q = 8-13) have been measured in an animated crossed-electron ion beam experiment. Ionization thresholds corresponding to particular electron pairs and inner-shell electron ejection are estimated from a structure Hartree-Fock calculation. For double ionization, results show that, along the homonuclear sequence, direct double ionization is progressively overcome due to the increasing relative importance of direct L-shell ionization followed by autoionization. The presence of ions in metastable states is observed for Kr8+ and Kr9+ contributing to direct and indirect processes