The Treatment of Energy Loss in Terms of Induced Current Density

Abstract

Abstract It is proved that the energy loss can be presented as a convolution of the electric force of the charged projectile with the density of the current induced in stopping media. This provides new possibilities in analysis and also in development of realistic models of the phenomenon. These possibilities are demonstrated in treatment of energy loss to free electrons. Particularly, the method provides a picture of spatial localization of the quantum effects. This helps to clear the origin of the higher order Barkas and Bloch corrections. The dielectric approach for a gas of interacting electrons can be also reformulated in terms of induced current. The combination of the two models permits to take into account simultaneously the higher order effects and the screening of the projectile field. Using additionally the approximation of local response, the method can be applied to describe the energy loss in ion–atom collisions. Finally, we discuss the features of electron dynamics which could result in significant correlation between the energy loss and the angle of deflection of the projectile.