COINCIDENCE MEASUREMENTS OF KRYPTON-KRYPTON COLLISIONS

In collisions of Kr+ ions with Kr atoms at keV energies, both particles from the same encounter are recorded in coincidence. The charge states m of the scattered particle and n of the recoil particle are measured, and the relative probability of such an (m, n) event is determined, together with the inelastic energy loss associated with that event. These data are analyzed using the statistically model of Everhart and Kessel. This model, which assumes m and n to be statistically independent of each other, fits the data fairly well. Ionization potentials for Kr+5 through Kr+9 are estimated from the data curves as interpreted by the statistical model. There is an active region in the Kr+ -Kr data at 25-keV incident energy and 9°scattering where the inelastic energy changes suddenly, and other anomalous effects are found. This is compared and contrasted with active regions previously found in Ne+ -Ne and Ar+ -Ar data. © 1968 The American Physical Society.