Laboratory Studies of Laser-Driven, Magnetized Collisionless Shocks*

We present results from experiments and simulations on the formation and evolution of quasiperpendicular collisionless shocks created through the interaction of a supersonic laser-driven magnetic piston and magnetized ambient plasma. Time-resolved, two-dimensional imaging of plasma density and magnetic fields shows the formation and evolution of a supercritical shock propagating at magnetosonic Mach number Mms ≈ 12. By directly probing particle velocity distributions, additional measurements reveal the coupling interactions between the piston and ambient plasmas that are key steps in the formation of magnetized collisionless shocks. Particle-in-cell simulations constrained by experimental data further detail the shock formation process, the role of collisionality, and the dynamics of multi-ion-species ambient plasmas. The development of this experimental platform complements, and in some cases overcomes, the limitations of similar measurements undertaken by spacecraft missions, and allows novel investigations of energy partitioning and particle acceleration by high-Mach-number shocks.