Perspectives on Recent Progress in Developing Ar K-shell Z-Pinch Sources

Various developments, including a three-plenum, ``pusher-stabilizer-radiator'' gas puff nozzle, have culminated in the doubling of achievable Ar K-shell yields on Sandia's Saturn generator, from 38 to 75 kJ. This was accomplished at comparatively long implosion times of $\sim $ 200 ns. This talk briefly reviews the more than 15 years of steady progress which brought this advance about. The Ar Z-pinches studied over that time have produced K-shell yields ranging from a few kJ on PITHON to $\sim $ 300 kJ on the Z generator. They have been analyzed with a consistent spectroscopic method in an effort to empirically ascertain what properties make such pinches good radiators. We also examine how much they depart from Bennett equilibrium.