Angular dose variations from 320 kV rod pinch diode flash X-ray experiments on the modified Kali-1000 Pulsed Power System

Abstract

This paper highlights the angular distribution of radiation dose emitted from a rod-pinch diode. The typical RP diode employed used a small diameter (1–2 mm) anode rod extended through a cathode aperture (5–8 mm). The diode chamber is maintained at 2 × 10–5 Torr vacuum by a rotary backed diffusion pump. Experiments performed on a modified Kali-1000 Pulsed Power System (300 kV, 30 kA, 100 ns) were aimed at optimizing the source by maximizing the figure of merit (dose at 1 m in rad/spot diameter2 in mm2) with minimizing of the diode impedance. The typical electron beam parameters used in the experiments are 240–320 kV, 6.5–27.5 kA, 100 ns, with a few hundreds of kA/cm2 current density. The radiation emitted from a rod-pinch diode is measured using thermoluminescence dosimeters at an angular interval of 15° on either side of the rod in horizontal and vertical plane with different aspects ratio ranging from 2.5 to 10.0. Experimentally found that the radiation dose produced from the rod pinch diode configuration is maximum in the axial direction and decreases with angular variation on either side of the axis in horizontal and vertical planes, which indicates the directivity of the source. Maximum radiation dose at 1 m distance on the axial line is ranging from 42 to 307 mR.