Pulsed-power magnetized shocks under an external magnetic field*

We present the results from our second experimental campaign with the goal of characterizing magnetized plasma jets and magnetized shocks on the Michigan Accelerator for Inductive Z-Pinch Experiments (MAIZE) in the Plasma, Pulsed Power, and Microwave Laboratory at the University of Michigan. We show the interactions of magnetized plasma jets created by conical wire-arrays and the behavior of shocks generated by collisions with a solid obstacle in the presence of an external magnetic field. We show how the structure and behavior of the shock layer, as well as flow instabilities, vary as a function of magnetic field strength. To generate the magnetized plasma flows, we used MAIZE to ablate 100-micron, aluminum wire arrays with currents in the order of 500 kA with a rise time of 250 ns. We use a conical array to drive an axial plasma jet, while an externally powered Helmholtz coil provides a uniform axial magnetic field which we can vary from 0.5 to 5 T. Our primary diagnostic consists of laser shadowgraphy (532 nm), captured by an intensified, fast framing camera, showing the structure and evolution of the plasma flow. In addition, preliminary results from a newly installed laser interferometry diagnostic identify density features that may correspond to a bow-shock layer.