X-ray emission from a plasma focus with high-Z inserts at the anode tip

Abstract

X-ray emission in different energy windows, from a low energy Mather-type plasma focus by employing high Z inserts at the anode tip is investigated. Quantrad Si pin diodes with differential filtering are employed as time-resolved x-ray detectors, whereas a pinhole camera is used for time-integrated analysis. The x-ray flux from the focus region is found to be measurable within the pressure range 0.25–3.5 mbar of hydrogen. The maximum emission in 4π-geometry is found to be 29.4±0.2 J, 3.43±0.05 J and 4.00±0.02 J with Pb, W and Mo inserted anodes, respectively, and corresponding wall plug efficiencies for x-ray generation are 1.28%, 0.15% and 0.2%. The x-ray emission is found predominantly as a result of electron beam activity on the anode tip, which is confirmed by the images recorded by the pinhole camera.