The MAGPIE dense Z-pinch project

Summary form only given. A design study was conducted on the Mega Ampere Generator for Plasma Implosion Experiments (MAGPIE), a project currently under construction to study radiative collapse of a dense Z-pinch plasma created from a 20-μm-diameter cryogenic hydrogen fiber. Detailed simulation of the generator performance when coupled to the fiber pinch has been carried out with both a 0-D and 1-D plasma code including radiation transport. Machine tolerances have been studied in the context of the ultimate achievable density. The rate of rise of current prior to the onset of the radiative collapse is found to be important, and a double bounce technique has been employed in the design of the transfer line to enhance the rate of current rise at late time, 1-D numerical simulations suggest that the shapes of radial profiles of the pinch column change significantly during radiative collapse. The high radiation emission region on axis becomes increasingly separated from the region of maximum ohmic heating near the surface, preventing the fall in current from terminating the collapse. Radiation transport and high density equation of state models show that the collapse is eventually terminated by a combination of opacity and electron degeneracy effects. Utilization of the double bounce voltage serves to increase the maximum current and the reservoir of vacuum magnetic pressure which does work on the plasma during collapse. Therefore, the temperature is kept high during collapse, delaying the onset of the termination processes and achieving higher density compression