Numerical Study on the Characteristics of Cylindrical Virtual Cathode Reflex Triode Array

The bremsstrahlung cylindrical virtual cathode reflex triode (CVCRT) array is a new type of pulsed warm X-rays load. In this article, we established the CVCRT particle model and simulated and analyzed the working process and the influence of structural parameters on impedance. The results show that the impedance of the CVCRT depends on the structure of electrode and the thickness of anode conversion target. The theoretical impedance calibration relation was given, and the impedance simulation results of particle simulation agree well with the theoretical solution. Based on the Monte Carlo (MC) code, the radiation model of the CVCRT was established, and the influence rule of anode conversion target on X-ray parameters was studied. Results show that the anode thickness is the main factor affecting X-ray intensity. Under the voltage of 300 kV, the optimum thickness of the anode is about 10 \mu m. The influence of array arrangement on the spatial distribution of radiation field was calculated. The CVCRT array can superpose the X-rays in the effective radiation region and improve the efficiency of X-ray utilization, and the intensity of X-rays is about 1.9 times higher than that of the cylindrical reflex triode (CRT) under the identical driving conditions.