Experimental and theoretical results on electron emission from helium by the impact of bare Li3+ ions

Abstract

We investigate experimentally and theoretically the ionization of helium atoms by the impact of bare Li3 + projectiles at intermediate and high incident energies. We report on measured absolute values of doubly differential cross-sections, as a function of the emitted electron energies and angles, at collision energies of 200 and 440 keV u−1. Different physical aspects of the reaction are interpreted theoretically by comparison of the data with quantum-mechanical continuum distorted wave and continuum distorted wave–eikonal initial state calculations as well as classical trajectory Monte Carlo simulations. There is an overall good agreement of the calculations with the experimental data, which improves considerably for higher collision energies.