Opacity and gradients in aluminum wire array z-pinch implosions on the Z pulsed power facility

Aluminum wire array z pinches imploded on the Z generator are an extremely bright source of 1-2 keV radiation, with close to 400 kJ radiated at photon energies >1 keV and more than 50 kJ radiated in a single line (Al Ly-alpha). Opacity plays a critical role in the dynamics and K-shell radiation efficiency of these pinches. Where significant structure is present in the stagnated pinch this acts to reduce the effective opacity of the system as demonstrated by direct analysis of spectra. Analysis of time-integrated broadband spectra (0.8-25 keV) indicates electron temperatures ranging from a few 100eV to a few keV are present, indicative of substantial temperature gradients. (C) 2014 AIP Publishing LLC.