Study of X-ray emission from a low energy (2.3 kJ) plasma focus by W-insert at the anode tip

Abstract

The X-ray emission from a low energy (2.3 kJ) Mather-type plasma focus operated with hydrogen filling is investigated. Specifically the X-ray emission in 5.0-9.0 keV and 13.0-25.0 keV energy range is studied by inserting a tungsten metallic disc at the copper tapered anode tip. Filtered pin diodes are used as time resolved X-ray detectors whereas a pinhole camera is employed for time integrated analysis. The X-ray flux from the focus region is observed measurable within the pressure range 0.25-3.5 mbar of hydrogen filling. The maximum emission in 4/spl pi/-geometry is estimated as 3.43 /spl plusmn/ 0.05 J and corresponding wall plug efficiency for X-ray generation is 0.15 %. The X-ray emission is found dominantly as a result of electron beam activity on the anode tip that is confirmed by the images recorded by the pinhole camera.