Energy loss of fast protons scattered from an Al(111)-surface under grazing incidence

Abstract

Protons with energies ranging from about 6 to 30 keV are scattered under grazing angles of incidence from a flat and clean Al(111)-surface. We observe angular and energy distributions of the scattered projectiles with high resolution and find for the mean energy loss a pronounced increase with projectile energy and a slight decrease for an increasing angle of incidence. We present model calculations based on the assumption that the energy loss is predominantly due to binary collisions with conduction electrons. These calculations reproduce main features of our data fairly well.