Plasma-filled paraxial diode operation on RITS-3

Summary form only given. In electron beam driven flash X-ray radiography, an electron beam is focused onto a high atomic number target to generate high dose X-rays while achieving small, 16 cm -3 , simulations show that the net currents are significantly reduced so that little beam sweep occurs, thereby achieving a smaller time-integrated spot. A plasma-filled version of the paraxial diode was devised and fielded on the RITS-3 accelerator at Sandia National Laboratories, operating at 4 MV. Several RITS shots were fired with plasma densities typically in the range of 10 15 -10 16 cm -3 , as well as with initially neutral gas (0.5 torr hydrogen and 1-5 torr air). Stable spot sizes were measured for several plasma-filled paraxial diode shots. Highlights from the spectroscopic survey are reported. Plans for future plasma-filled paraxial diode investigations are also presented