Nonresonant Electron Transfer and ProjectileK-Electron Excitation in Ion-Atom Collisions

Abstract
Evidence is presented for nonresonant and resonant electron transfer and projectile K x-ray excitation in 15-94-MeV Si11+ + He collisions. In the former, the projectile K electron is excited by the Coulomb field of the target nucleus, and a target electron is captured. In the latter, the electron-electron interaction gives rise to the resonant process. The nonresonant process reached its maximum cross section at ∼20 MeV, while the resonant process peaked at ∼85 MeV, in agreement with theory.