Relativistic high-current electron-beam stopping-power characterization in solids and plasmas: collisional versus resistive effects

We present experimental and numerical results on intense-laser-pulse-produced fast electron beams transport through aluminum samples, either solid or compressed and heated by laser-induced planar shock propagation. Thanks to absolute Kyield measurements and its very good agreement with results from numerical simulations, we quantify the collisional and resistive fast electron stopping powers: for electron current densities of � 8 � 10 10 A=cm 2 they reach 1:5 keV=� m and 0:8 keV=� m, respectively. For higher current densities up to 10 12 A=cm 2 , numerical simulations show resistive and collisional energy losses at comparable levels. Analytical estimations predict the resistive stopping power will be kept on the level of 1 keV=� m for electron current densities of 10 14 A=cm 2 , representative of the full-scale conditions in the fast ignition of inertially confined fusion targets.