Theoretical initial l dependence of ion-Rydberg-atom collision cross sections

Classical trajectory Monte Carlo calculations have been performed for ion-atom collisions in the velocity matching region for target Rydberg states of given specific n and l. A classical ensemble derived previously is used, which corresponds to the set of hydrogenic quantum states of fixed n and l. Substantial dependence on the initial l value is found for charge transfer, ionisation, and excitation cross sections. For charge transfer, the distributions over the final n' show peaks in substantial agreement with a recent experiment of Rolfes and MacAdam (1982). Experimental data for the other processes are not yet available.