Interaction of slow ions with matter

Abstract

The problem of energy losses suffered by energetic ions moving in condensed matter with velocities smaller than the Fermi velocity is studied from different viewpoints. For protons, comparison between linear dielectric theory results and those obtained by means of a scattering approach is made. Within the latter we present calculations performed for different parametrized model potentials together with those derived from a fully self-consistent potential obtained within the density functional formalism to treat the many-body response of the electron gas. Comparison with experimental data is also presented. For ions with higher nuclear charge (Z1) our results reproduce the oscillations of the stopping power, and the straggling parameter, as a function of Z1. Results obtained by going beyond the random phase approximation description of the density of states at the Fermi level are presented as well. Finally we present the results of a calculation of the stopping power of aluminum for protons as a function of velocity with explicit inclusion of the contributions from different charge state fractions together with the energy loss associated with the process of capture and loss itself.