Investigation of an 8-CM Diameter, Neon Gas Z-Pinch

Summary form only given. Neon Z-pinch experiments on Hawk (0.6 MA, 300 ns implosion time) use a Titan Pulsed Sciences Division double-shell gas-puff valve and nozzle. The outer diameter of the gas distribution is about 8 cm and the axial length of the Z-pinch is 4 cm. Each nozzle is fed by a separate plenum. For equal fill pressures, each nozzle contributes about half the mass load in the pinch. We examine the effect of different gas density profiles on the quality of the pinch. The initial results reported in 2004, indicating that the K-shell radiation efficiency peaked at P_inner+P_outer=110 torr with P _inner=90 torr, are validated. In addition, analysis of the current and local voltage measurements suggest that the peak power delivered to the load near the time of peak K-shell emission can be a useful electrical figure of merit for the quality of the pinch stagnation. Radiation diagnostics include X-ray diodes to measure time dependent K-shell power and yield, a pinhole camera to image the pinch in the K-shell region and a multidetector array to measure the axial dependence of the radiation. Also, the imploding plasma is diagnosed using a two-dimensional holographic interferometer that produces images at two times during a single shot