A plasma opening switch for PRS loads on Double-EAGLE

Summary form only given. The next generation of pulsed power drivers will likely have much longer current pulse lengths than the present generation, 200-300 ns as compared to 50-100 ns. This presents the problem of efficiently connecting FRS loads, which have been optimized for the shorter pulses, to the longer pulse drivers. One approach has been to develop PRS sources that can be directly driven by the longer current pulse without suffering from the Rayleigh-Taylor instability. While this has met with some success, the radiation efficiency (kJ/MA) is only /spl ap/50% of that produced in short pulse. Another approach that we investigated, and report upon here, is to use a large volume, low density, plasma opening switch to conduct the full current for /spl ap/100 ns and then open, transferring the current to the PRS load. The resultant drive pulse seen by the PRS is thus comparable to that produced by short pulse drivers. For the experiments reported here, the Double-EAGLE current pulse was lengthen to 250 ns by shorting out switches in the waterlines.