EFFECT OF ANODE AND INSULATOR MATERIALS ON PLASMA-FOCUS SHEATH (PINCH) CURRENT

Plasma sheath (pinch) current in a low energy (2.2 kJ) plasma focus de vice was measured for different anode and insulator materials, Among t he anode materials, the highest sheath current was observed with tungs ten and the lowest with aluminum, Among the ceramic insulators the max imum plasma sheath current was obtained with quartz and the minimum wi th alumina, The computed high Z (atomic number) impurities in plasma s heath, however, were least in the plasma focus with alumina insulator, None of the nonceramic (plastic) insulators produced neutrons, as the plasma sheath was nonuniform and mas highly contaminated with impurit ies.