High-power laser experiment forming a supercritical collisionless shock in a magnetized uniform plasma at rest

TL;DR

This paper introduces a novel experimental approach to generate and analyze supercritical collisionless shocks in a magnetized plasma using laser-driven plasma ablation, with results supported by simulations and optical diagnostics.

Contribution

It demonstrates a new method to produce and observe supercritical collisionless shocks in a controlled laboratory setting, combining experimental techniques with simulations.

Findings

Successful generation of supercritical collisionless shocks in the lab

Identification of reflected ion edges in the shock structure

Agreement between experimental results and particle-in-cell simulations

Abstract

We present a new experimental method to generate quasi-perpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well-magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counter-streaming magnetized N flows. Namely we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.