The effect of gradients at stagnation on K-shell x-ray line emission in high-current Ar gas-puff implosions

Argon gas puffs have produced 330 kJ +/- 9% of x-ray radiation above 3 keV photon energy in fast z-pinch implosions, with remarkably reproducible K-shell spectra and power pulses. This reproducibility in x-ray production is particularly significant in light of the variations in instability evolution observed between experiments. Soft x-ray power measurements and K-shell line ratios from a time-resolved spectrum at peak x-ray power suggest that plasma gradients in these high-mass pinches may limit the K-shell radiating mass, K-shell power, and K-shell yield from high-current gas puffs. (C) 2015 AIP Publishing LLC.