Operation of a heated POS IN DM1

Summary form only given. DM1, located at Maxwell Physics International (MPI), is DTRA's test bed for its innovative flash X-ray simulator DECADE. One quarter of this is presently being delivered by MPI to the Arnold Engineering and Development Center (AEDC). DMI's low cost design has a water transfer capacitor followed by a plasma opening switch that shortens the microsecond Marx discharge into the desired 40 ns wide hard X-ray pulse. A detailed assessment of DM1 operation has indicated current loss between the POS and load The losses could include parasitic ion currents from plasma in the diode, and unintended POS plasma generated from the electrode surfaces in the switch. These plasmas could come from the electrode surfaces: hot electrodes are intended to minimize plasma evolution from the electrodes. We are presently designing an experiment with electrodes heated to a temperature exceeding 800 K in a way that is consistent with discharge cleaning. We expect to present results from shots with hot electrodes. We anticipate improvements similar to the delayed impedance collapse in the bremsstrahlung diode heated by Pereira and Fisher at NRL (1999?), and the lower jitter in a heated high power magnetron observed by Price et al. at MPI (1998). Attacking the surface plasma problem has also been very successful in suppressing parasitic current in ion diodes (Cuneo et al., 1997).