Study of the x-ray emission scaling law in a low energy plasma focus

The performance of a low energy (0.6-1.8 kJ) Mather-type plasma focus (PF) device as a Cu-Kα x-ray source is examined. The Cu-Kα and total x-ray emissions are measured for argon and hydrogen filling. It is found that Cu-Kα emission varies as YK [J] ∼ [E(kJ)]3.5-4.5 ∼ [I(100 kA)]3.5-4.5, whereas the total x-ray emission is found to follow Ytot [J] ∼ [E( kJ)]4.5-5.5 ∼ [I(100 kA)]4.5-5.5. At optimum conditions, the system with discharge energy of 1.8 kJ is found to generate x-rays with 1.44 ± 0.07% efficiency. About 32% of the emission constitutes the Cu-Kα line radiation. With a cut at the anode tip, the x-ray flux in the side-on direction is increased three times. The modified geometry may help in using the PF as a radiation source for x-ray diffraction. (brief communication)