The effect of pre-ionization on improving the performance of mather type plasma focus device MTPF2.4kj

The impact of pre-ionization using a 330 MΩ shunt resistor on the performance characteristics of a Mather Type plasma focus device with 2.4 kJ of energy, charged by a 12 μF capacitor bank to a maximum voltage of 20 kV, will be discussed in relation to hydrogen gas. In this study, the signal characteristics of the current and the current derivative of the device were measured and compared with and without pre-ionization at an optimal operational pressure of 0.85 Torr. Additionally, the emitted hard X-rays and ion beam in each shot were measured using a Ne102 X-ray plastic scintillation detector and Faraday cup, respectively. These measurements were conducted and compared with and without pre-ionization at the optimal pressure. The results from the current and current derivative signals of the device indicate that with initial pre-ionization, the signals exhibit a deeper and sharper fracture at the pinch time compared to when the pre-ionization circuit is inactive. This suggests that a stronger and more defined pinch occurs with pre-ionization. Furthermore, analysis of the Faraday cup signal amplitudes reveals that the intensity of emitted hard X-rays is significantly higher when pre-ionization is utilized compared to when it is not. Therefore, pre-ionization markedly enhances the efficiency of the plasma focus device, increases the intensity of emitted hard X-rays, and generates an ion beam with a higher current.