An investigation of the ion beam of a plasma focus using a metalobstacle and deuterated target

The results of an experimental study of the ion beam properties of a 3.3-kJ, 15-kV plasma focus are reported. The plasma focus is operated at 3 torr deuterium, and neutron yield measurements are made with a copper obstacle or deuterated target placed at various axial positions from the end of the anode. It is found that in the normal operation of the focus without an obstacle or target, less than 15% of the neutrons are produced within the pinch column, and that more than 85% of the neutrons arise from the deuterium-ion-beam bombardment of the deuterium gas in the region 20-60 mm from the end of the anode. The neutron production is highest between 30-40 mm from the anode. The results are valid only for a small focus