Depleted uranium (92U238) induced preionization for enhanced and reproducible x-ray emission from plasma focus

The effect of preionization induced by depleted uranium (U-92(238)) around the insulator sleeve on the x-ray emission of (2.3-3.9 kJ) plasma focus device is investigated by employing Quantrad Si p-i-n diodes and a multipinhole camera. X-ray emission in 4 pi geometry is measured as a function of charging voltage with and without preionization. It is found that the preionization enhances Cu K alpha and total x-ray yield about 100%, broadens the x-ray emission pressure range and x-ray pulse width, and improves shot to shot reproducibility of plasma focus operation. The pinhole images of x-ray emitting zones indicate that dominant x-ray emission is from the anode tip. (c) 2006 American Institute of Physics.