Impact-Parameter Dependence of the Electronic Energy Loss of Protons in Solids

We calculate the electronic energy loss of the low- and intermidiate-energy proton in collision with a solid atom as a function of the impact-parameter by using the linear-response dielectric theory, the semiclassical approximation and local electron density approximation. The correlation and exchange interaction of the electron gas in solids is taken into consideration by using a local-field-correction dielectric function. With the formalism we also calculate the electronic stopping cross section of protons in solids.