Influence of magnetic probe presence on current sheath dynamics in plasma focus operation

Abstract

The effects of the magnetic probe presence near the focus region on the current sheath dynamics are studied. The system consists of a single 32μF, 15 kV (3.6 kJ) capacitor. It is found that the current sheath during the radial collapse phase strongly interacts with the magnetic probe jacket (Pyrex glass tube of diameter 5.7 mm) and climbs over it up to several centimeters. X-ray images recorded for argon pressure range of 0.25 – 3.25 mbar clearly indicate that the size as well as the intensity of the X-ray source is significantly enhanced compared to the case ehen no probe is inserted in the system. Generally, the hot spots are formed up to about 30 mm above the anode tip and are only rarely observed 75 mm above the anode tip, which is probably due to the refocusing of the current sheath at that height. These preliminary results suggest that using some suitable material, the path of the current sheath can be diverted to any desired direction and then guided to converge at a preselected point.