Effect Of Insulator Sleeve Length On Neutron Yield In A 4.4 kJ Dense Plasma Focus Device

The deuterium-fill Dense Plasma Focus (DPF) is a Z-pinch configuration that produces energetic ions, X-rays, and neutrons from a high-temperature and high-density plasma pinch. There have been limited studies that consider the impact of the insulator length on the resulting pinch quality and neutron production. Experiments were conducted on a 4.4 kJ (250 kA, 21 kV) Mather type DPF 1 with laser probing diagnostics and a Be-activation detector for three different insulator sleeve lengths. Here, we report the results of experiments to optimize the neutron yield as a function of insulator sleeve length and fill pressure. The results show that the insulator length plays an important role in the dynamics, including pinch timing and neutron yield: increasing the insulator length reduces the effective anode length and thus affects the optimal fill pressure.