Laboratory plasma physics experiments using merging supersonic plasma jets

TL;DR

This paper details laboratory experiments at Los Alamos using merging supersonic plasma jets to study jet interactions, shocks, and plasma dynamics in various regimes, advancing understanding of plasma physics phenomena.

Contribution

It introduces a versatile experimental setup for merging plasma jets with variable species and parameters, enabling new investigations into plasma interactions and shock formation.

Findings

Jets achieve velocities of 30-100 km/s

Shocks form during jet merging in different regimes

Experiments explore both collisional and collisionless interactions

Abstract

We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven rail guns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: $n_e\approx n_i \sim 10^{16}$ cm$^{-3}$, $T_e \approx T_i \approx 1.4$ eV, $V_{\rm jet}\approx 30$-100 km/s, mean charge $\bar{Z}\approx 1$, sonic Mach number $M_s\equiv V_{\rm jet}/C_s>10$, jet diameter $=5$ cm, and jet length $\approx 20$ cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.