Experimental Design of a Magnetic Flux Compression Experiment

Generation of ultrahigh magnetic fields is an interesting topic of high-energy-density physics, and an essential aspect of Magnetized Target Fusion (MTF). To examine plasma formation from conductors impinged upon by ultrahigh magnetic fields, in a geometry similar to that of the MAGO experiments, an experiment is under design to compress magnetic flux in a toroidal cavity, using the Shiva Star or Atlas generator. An initial toroidal bias magnetic field is provided by a current on a central conductor. The central current is generated by diverting a fraction of the liner current using an innovative inductive current divider, thus avoiding the need for an auxiliary power supply. A 50-mm-radius cylindrical aluminum liner implodes along glide planes with velocity of about 5 km/s. Inward liner motion causes electrical closure of the toroidal chamber, after which flux in the chamber is conserved and compressed, yielding magnetic fields of 2–3 MG. Plasma is generated on the liner and central rod surfaces by Ohmic heating. Diagnostics include B-dot probes, Faraday rotation, radiography, filtered photodiodes, and VUV spectroscopy. Optical access to the chamber is provided through small holes in the walls.