Dependence of Plasma-Filled Diode Operation on Initial Plasma Distribution

Summary form only given. A plasma filled diode (PFD) can produce higher X-ray dose rates than a conventional vacuum bremsstrahlung diode. It is of interest to understand how the injected plasma distribution affects the PFD and, if possible, to tailor the injected plasma distribution to optimize the PFD dose rate. This paper reports on an experimental spatial-temporal interferometric mapping of the plasma injected into a PFD. The plasma is created by discharging a capacitor through a coaxial plasma gun located on axis perpendicular to the anode foil. The plasma from the gun is collimated by a 1-cm diameter cathode tube. The plasma map was done using a 40 MHz heterodyne optical ribbon interferometer at lambda = 532 nm in a test stand, and PFD performance was tested on GAMBLE II with in situ measurement of the initial axial density distribution. Preliminary results show that highest dose rates occur when the plasma density axial distribution is closest to constant