Resistive diffusion and radiative cooling effects in magnetized oblique shocks

Magnetized oblique shocks are of interest in various plasmas, including in astrophysical systems, magneto-inertial confinement fusion experiments, and in aerospace applications. Through experiments on the COBRA pulsed power facility (Cornell University, 1~MA peak current, 100~ns rise time), we investigate oblique shock formation in a system with a magnetic field, and where both radiative cooling and resistive diffusion are important. Compared to previous pulsed power experiments, which have investigated quasi-parallel oblique shocks, here we consider perpendicular-type shocks, which can support magnetic field compression. In our experiments, supersonic, super-Alfvénic, collisional plasma flows, generated using an aluminum exploding wire array, are deflected by angled obstacles to generate oblique shocks. The shocks are imaged using laser shadowgraphy and Mach-Zehnder interferometry, while optical Thomson scattering provides measurements of the flow velocity and temperature. The shocks exhibit shallower shock angles and higher density compression, when compared to canonical Rankine-Hugoniot predictions. These results are best described by a model that includes both resistive diffusion and radiative cooling, consistent with the values of the cooling parameter and the resistive diffusion length in the experiment.