Projectile polarization effects in the energy loss of swift ions in solids

We have evaluated the energy loss of swift hydrogen ions moving through a solid target, paying special attention to the effect due to the polarization of the projectile. Our calculation is done in the framework of the dielectric formalism, taking into account the contribution to the energy loss due to the charge fraction of protons and hydrogen atoms, the electronic capture and loss processes, and the polarization of the projectile. The electronic structure of the projectile is described by a hydrogen-like model screened by the target electrons. We have found that the polarization of the projectile is a non-negligible contribution to the energy loss of the hydrogen atoms in the energy range around the maximum of the stopping power. The calculated stopping power (accounting for all the above mentioned effects) agrees satisfactorily well with the experimental data in a wide projectile velocity region. (C) 2002 Elsevier Science B.V. All rights reserved.