Hot microplasmas collected as a hard X-ray source

The authors study, experimentally, high power density matter (HPDM) of hot microplasmas collected in the interelectrodes space in a discharge at “commercial” vacuum, and the hard X-ray yields related. In particular, a Marx generator (under just 1 J stored energy) triggers a discharge through a 50 Ω transmission cable in a hollow cathode geometry. The appropriate choice of anode and cathode configurations and their efficient combination with some gas fulfilment may provide the consequent manipulation both with cold solid density grains of anode material, and hot microplasmas originating from them after breakdown. Dynamic structures of hard X-ray from plasmas “dust” were registered using a sensitive imaging device with 5 ns exposure time. The numbers of X-ray spots registered beyond of electrodes were up to few hundreds per shot. The results for single grain (cluster) overheating and explosion accompanied by X-rays seem similar to recent data on high-intensity laser (10^15-18 W/cm ²) focusing on clusters. However, hard X-ray emission efficiency registered and well reproduced in these discharges (0.1-0.3%) seems essentially higher