Argon Z-pinch implosions on Phoenix

Summary form only given, as follows. Upgrades to the Phoenix front end have resulted in a three-fold increase in Argon K-shell X-ray yields. Lack of a transit time isolator between the center conductor and ground necessitated powering the gas-puff hardware with batteries and supplying control via fiber optic cables. A simple gas flow model was developed to optimize the valve/nozzle design. The gas-puff valve and nozzle were modified to produce a 250-/spl mu/s density rise time. This short rise-time allowed firing on the gas plateau which improved reproducibility. Front end power flow was improved by opening the MITL from 8 to 10-mm and by increasing the dog-leg at the nozzle to obstruct UV light. The highest yield shots were achieved with a 4-cm long load using a 3.5-cm mean diameter nozzle with a mean inward tilt of 13.75 degrees. X-ray pulse widths ranged between 7-15 ns and X-ray pinhole photos suggest uniform assembly on axis. Results and documentation of the Phoenix upgrades are presented.