Investigation of radiative bow-shocks in magnetically accelerated plasma flows

Summary form only given. We present a study of the formation of bow shocks in radiatively cooled plasma flows. This work uses the XP generator (260kA, 145ns) at Cornell University to drive an inverse wire array. This generates a quasi-uniform, large scale hydrodynamic flow accelerated by Lorentz forces to Ma > 1. This flow impacts a stationary object placed in its path, forming a well-defined Mach cone. Collinear interferogram and gated-self emission diagnostics demonstrate that the cone angle with distance from the wire decreases (increasing Mach number) and is indicative of a strongly cooling flow. Rapid density increase from the background flow into the object is indicative of a strong density jump at the shock. High resolution self-emission imaging shows the formation of a thin (<;60 μm) strongly emitting shock region where Te~50eV, indicating rapid cooling behind the shock. In addition, emission is observed upstream of the shock position which may be consistent with the formation of a radiative precursor. Data compare well to analytical calculations of the expected scale-lengths of both the precursor and cooling regions, and initial simulation work will also be presented.