Stopping of Relativistic Electrons in Partially Degenerate Electron Fluid

The stopping mechanisms of relativistic electron beams in superdense and partially degenerate electron fluid targets are investigated in framework of the fast ignitor concept for ICF. We focus attention on target partial degeneracy parameter Theta=Te/Tf. The target electron fluid is thus accurately modelled with a RPA dielectric function. Stopping is seen as steadily increasing with Theta. For electron projectile energies below 2-4 MeV, according to target densities, stopping power decays a la Bethe i.e in 1/Vp$^2$, with Vp, projectile velocity. At higher energies, stopping increases steadily with Vp in a quasi- logarithmic fashion, characteristic of the ultra-relativistic regime.