Two- and Three-Body Effects in Single Ionization of Li by95MeV/uAr18+Ions: Analogies with Photoionization

Abstract
International audienceCross sections for single electron emission have been measured in collisions of 95MeV/u Ar18+ with atomic Li for electron energies 5–1000 eV and angles 25°–155°. The high projectile velocity made possible the separation of two- and three-body processes in the angular distributions of the ejected electrons. Low-energy emission of the 2s electrons is found to be significantly influenced by two-body effects and, furthermore, the node in the Li 2s wave function manifests itself in the angular spectra. Emission of 1s electrons is attributed mainly to three-body effects. The two- and three-body processes are associated with Compton scattering and photoabsorption, respectively