Elastic and inelastic collision of low energy proton scattering from rare gas solids

We have carried out the systematic measurements of energy spectrum for low energy (50-500 eV) proton scattering from rare gas solids of Ar, Kr and Xe. The observed energy spectra showed a multiple peak structure. The multiple peaks have been ascribed to the multiple inter-band electronic excitations, from valence to conduction band of the rare gas solid. In addition, each peak exhibited an asymmetric shape with a long tail toward the low energy side. In order to study these feature of spectrum, we develop a simple statistical model. This model involves three physics parameters: the average number of close collisions C, the electronic excitation probability p, and the asymmetry index α. From C and p, the electronic stopping power can be estimated, whereas from α, the nuclear stopping power can be estimated.