Enhanced and reproducible neutron emission from a plasma focus with pre-ionization induced by depleted uranium (U238)

The effect of pre-ionization induced by depleted uranium (92U238) around the insulator sleeve on the neutron emission of (1.8-3.3 kJ) plasma focus device is investigated by employing time resolved and time integrated neutron detectors. The maximum average neutron yield of 2.5 x 108 is recorded at 3.5 mbar without pre-ionization, which increases up to 3.85 x 108 with pre-ionization. It is found that the pre-ionization enhances neutron yield, about (50 ± 5)%, broadens the neutron emission pressure range and improves shot-to-shot reproducibility of plasma focus operation for neutron emission. The pinhole images of charged particles emitting zones indicate that the pre-ionization increases the high temperature plasma volume