Argon Z-pinch experiments with large diameter nozzles

Summary form only given. We have developed large diameter nozzles for long-implosion-time argon z-pinch experiments over the past several years. Results on the Double-EAGLE generator in 2002 with a 12 cm double-shell nozzle (outer shell between 5 and 6 cm; inner shell between 2 and 3 cm) indicated that increased K-shell yield might be obtained with the addition of more mass near the axis, which was implemented by use of a central jet that was connected to the inner shell plenum. In our present work, we have modified the gas valve design by including a third plenum for the central jet. This allows the pressure to be set independently to maximize the K-shell yield and for a separate tracer gas to be introduced that can distinguish plasma parameters between gases originating in the central jet and the inner shell. Experiments utilizing this new system will occur in early 2004. In this paper, we discussed the design and detailed results of the experiments.