Magnetically driven plasma jet experiment on the Big Red Ball*

The complex morphology and formation of astrophysical jets on all scales remains obscure due to observational limitations. The MHD scalability of numerical simulations and laboratory plasma jets to astrophysical jets offers to bridge this gap. We are generating a magnetic-tower model of nonrelativistic plasma jets driven by magnetic fields having both toroidal and poloidal components, on the Big Red Ball (BRB), a 3m diameter spherical chamber, at the Wisconsin Plasma Physics Laboratory (WiPPL). We aim to study the propagation dynamics, collimation, and stability, mainly the kink and Rayleigh-Taylor instabilities, of these magnetically driven plasma jets. Prior experiments developed jets in vacuum backgrounds and smaller chambers. Our goal is to launch plasma jets in pressurized plasma background and investigate the formation of shocks and their precursors between the magnetized jet and the unmagnetized background plasma and how the development of the kink instability could depend on the background pressure. Our experimental configuration comprises bias field coils generating poloidal magnetic fields and a plasma gun consisting of neutral gas-puff drives and a disc-shaped cathode with a coplanar annulus-shaped anode with high voltage difference across them. We will present the preliminary results of the characterization of plasma jets from time and space resolved measurements of plasma parameters, including magnetic field, electron and ion densities, temperatures, and velocities.