Observation of Collisionless Shocks in Laser-Plasma Experiments

Abstract

The propagation in a rarefied plasma ($n_e\lesssim {10}^{15}{\mathrm{cm}}^{-3}$) of collisionless shock waves and ion-acoustic solitons, excited following the interaction of a long (${\tau }_L\sim 470\mathrm{ps}$) and intense ($I\sim {10}^{15}\mathrm{W}{\mathrm{cm}}^{-2}$) laser pulse with solid targets, has been investigated via proton probing techniques. The shocks’ structures and related electric field distributions were reconstructed with high spatial and temporal resolution. The experimental results were interpreted within the framework of the nonlinear wave description based on the Korteweg–de Vries–Burgers equation.