Ionization of noble gas by impact of hydrogen anions

Relative cross-sections for double ionization and single ionization of targets under the impact of hydrogen anions were measured. Two systems were investigated, H− projectiles with Kr and Xe targets. The energy region was 10–30 keV. Recoil ions originated from target (Kr+, Kr2+, Xe+, Xe2+) were detected in coincidence with projectiles in several final charge states (q = 0 and q = + 1). We compare the present results with the previous results of Ar. The results show that the cross-section ratios, taken between double and single ionization of Ar, Kr and X in the channels of single and double electron loss of H−, become larger and larger with the incident energy increasing, and that the cross-section ratios will cross at some certain energy for the two different electron loss channels. The crossing energy for Xe is about 23 keV