Modeling of Plasma Formation and Evolution on the Surface of Ohmically Heated Conductors

Abstract

The surface response to MG fields is important for eventual Magnetized Target Fusion (MTF) experiments " . Recent radiation-hydro numerical simulations in a planar geometry by Garanin et al. show how plasma can be generated through thermal processes on a metal surface. Experiments to study metal plasma formation and stability on the surface of typical liner materials in the MG regime are underway at the University of Nevada at Reno (UNR). Additional experiments on larger facilities such as Atlas and Shiva Star are also planned. We present here our initial modeling of the surface response of aluminum cylindrical conductors, assuming experimentally relevant current rise-times, which determine the ratio of current skin depth relative to conductor radius. Important effects include plasma formation, radiation transport, and the unstable m=0 mode driven by curvature of the magnetic field that holds the surface plasma against the metal. The sensitivity of results to various equation-of-state and resistivity models is also discussed.