Demonstration of current doubling and pulse sharpening on saturn

Summary form only given. Electrically driven flux compression was demonstrated on the Saturn Accelerator pulsed power driver at Sandia National Laboratories. Proprietary 16-cm-long ´skinny-armature´ re-entrant flux-compression cartridges were installed on Saturn to amplify and sharpen the current into a 3-nH static inductive load. In three campaigns eight shots were tried, each with different combinations of Saturn configuration, cartridge design, and operating parameters. In each shot, a few of the 36 Saturn modules provided seed magnetic flux by a secondary current in the Saturn long-pulse mode. The primary Saturn current drove an imploding wire-array plasma, which compressed the seed magnetic flux. In half the shots, the primary current was delayed and shortened with respect to the secondary current. In the best shot, a Saturn primary current of 3.1 ?? 0.3 MA was doubled to 6.3 ?? 1.0 MA in the load, quadrupling the load energy, and the 200-ns rise time of the Saturn primary current was sharpened to about 100 ns in the load. The late time at which the load current peaked in three of the shots, including the best shot, suggests a new phenomenology within the flux-compression cartridge, including a naturally occurring plasma opening switch. By amplifying currents and sharpening pulse widths on slow, low-voltage machines, magnetic-flux compression can potentially slash the cost of next-generation pulsed power drivers and save hundreds of millions of dollars in the future national investment in radiation simulators and Z-pinch- driven inertial confinement fusion for energy production. Moreover, the DTRA/Starmark Edifice Code suggests that flux-compression can be an enabling technology for titanium K-shell radiation from small, low-risk loads. We are grateful to Bart Stewart at AEDC for valuable advice, encouragement, and support, and to Brad Peyton and the Saturn operations crew at Sandia.