Magnetic stagnation of two counterstreaming plasma jets induced by intense laser

TL;DR

This study reports the first direct experimental observation of magnetic stagnation and redirection of counterstreaming laser plasma jets induced by ultra-intense laser pulses, advancing understanding of plasma interactions relevant to astrophysics.

Contribution

It provides novel experimental evidence of magnetic field-induced stagnation in counterstreaming plasma jets, supported by hybrid modeling that includes kinetic ion effects and electron pressure evolution.

Findings

Observation of plasma flow stagnation and redirection due to magnetic fields

Demonstration of magnetic field compression in plasma interactions

Validation of hybrid PIC-fluid modeling for plasma jet behavior

Abstract

Experiments with interacting high-velocity flows of laser plasma can help answer the fundamental questions in plasma physics and improve the understanding of the mechanisms behind astrophysical phenomena, such as formation of collisionless shock waves, deceleration of accretion flows, and evolution of solar (stellar) flares. This work presents the first direct experimental observations of stagnation and redirection of counterstreaming flows (jets) of laser plasma induced by ultra-intense laser pulses with intensity $I \sim$ 2 $\times$ $10^{18}$ $W/cm^2$. Hybrid (PIC - fluid) modeling, which takes into account the kinetic effects of ion motion and the evolution of the pressure tensor for electrons, demonstrates the compression of counterdirected toroidal self-generated magnetic fields embedded in the counterstreaming plasma flows. The enhancement of the toroidal magnetic field in the interaction region results in plasma flow stagnation and redirection of the jets across the line of their initial propagation.