STOPPING OF IONS AND LOCAL ELECTRON-DENSITIES AT STRONG-COUPLING

We employ molecular dynamics (MD) computer simulations to investigate ions in electron plasmas at strong coupling. We observed in this regim e a stopping power of highly charged ions at low velocities which scal es with the charge like Z(1.5). This clearly deviates from the Z(2) ln (const./Z) scaling of the conventional weak coupling theories and is c onnected with a strongly enhanced local density of electrons around th e ions which is caused by the trapping of electrons in high Rydberg st ates due to multi-particle collisions occurring at strong coupling. Fo r the parameters corresponding to the less strongly coupled situation in an electron cooler we find a moderate enhancement of the local elec tron density created under the influence of the external magnetic fiel d.