Study of the electrode material and insulator length effect on high-energy X-rays emitted by a 4-kJ plasma focus device

Abstract

In this paper, behavior of hard X-ray (HXR) anisotropy and its intensity along the anode bar of the APF plasma focus device (16 kV, 36 μF, 115 nH) with different anode tip materials is studied. The signals obtained by scintillation detectors by a special arrangement at each angular position show that the employment of higher Z anode insert materials not only increases the intensity of HXR signal, but also results in the high degree of HXR emission isotropy. The highest HXR intensity was observed with a conic W anode insert and the lowest, with a flat Al anode insert. The side-on emitted intensity along the anode bar has been studied by moving the scintillation detector in the direction of the central electrode axis. For Pyrex and quartz insulators, the lengths of 40 and 50 mm, respectively, would seem optimal to produce the maximum HXR intensity. Also the Pyrex insulator would cause a higher HXR intensity than the quartz insulator.