Energy loss of keV He^2+ scattered off an A1(110) surface

This paper presents results of measurements of energy loss suffered by He-projectiles scattered off an Al surface. The measured loss distributions are modeled in terms of the (classical) friction experienced by the projectiles due to their interaction with the electron gas at the Al surface. Simulations of trajectories followed by the projectiles along the target surface were carried out, to extract the energy loss per unit distance (“stopping power”) and its width (“straggling”). Thus, the obtained numbers allow – for the first time – for a quantitative assessment of theoretical data.