Abstract
The inelastic energy loss Q has been measured for Kr+-Kr single collisions at incident energies of 20 and 30 keV and scattering angles ranging from 6° to 15°. For distances of closest approach r0 around 0.385 Å, the inelastic energy-loss distribution is triple peaked, and the differences in energy between the three peaks are independent of r0. This structure is interpreted as being due to the production of one or two MIV,V vacancies.