A Comparison Of Argon Gas Puff And Wire Array Implosions on the 4-MA, 6- TW Double-EAGLE Generator

We have recently extended yield radius scaling experiments from aluminum, and nickel wire arrays to argon gas puff implosions. The argon results, have shown that by producing a thinner shell (5 mm at the exit) with a 10 degree inward tilt, the 3 keV radiation yield increases from 4kJ to 13kJ, for a 2.5cm diameter nozzle. In addition to the increased yield, the pulsewidth decreases from 26 ns to 9 ns. Time-resolved pinhole images show that the zipper effect is removed. We estimate that the mass loading is in the range of 45 to 60μg/cm for the 2.5 cm diameter implosions. Following the prescription for the eta parameter by Whitney et al, we calculate eta to be in the range of 1.6 to 2.8 for the 2.5 cm diameter nozzles. When the nozzle diameter is increased to 4 cm and eta is pushed to 4, the argon K-shell yield decreases to around 9 kJ. We will present this data along with a comparison of our previous wire array data. The wire data has no evidence of a zipper, yet the pulsewidths are 30ns or so. We will also compare the experimental results to lD and 2D numerical simulations.