A model for energy loss and straggling of slow ions in electron gas with intraband exchange

Influence of ferro-paramagnetic phase transition on the electronic energy loss and the straggling of ions in the electron gas subjected to magnetic ordering is reported. The linear response (LR) theory was used in application to low velocity ions. The medium was described by the Lindhard dielectric function ε(k,ω). The magnetic interactions were included in the model by means of the Stoner treatment of itinerant electrons. The intraband exchange interaction was shown to shift the energy levels, change degeneracy, shift the Fermi level and thus contribute to the change of electron gas stopping characteristics. Results of the calculations were critically compared to change of stopping at the Curie temperature measured for Ni and Gd foils in transmission experiments.