Plasma formation in the wire array Z-pinch

Summary form only given. A series of experiments have been carried out on MAGPIE (Mega Ampere Generator for Plasma Implosion Experiments) to study the plasma formation in wire array z-pinches. The generator was operated at peak currents up to 1.4 MA with a rise time of 150 ns. Arrays of 16 mm diameter composed of between 8 and 32 aluminium and tungsten wires were used. Wire diameters were between 4 and 10 ym for tungsten and between 15 and 25 /spl mu/m for aluminium. Arrays with equally spaced wires as well as with variable inter-wire separation were studied. To study the dynamics of the plasma, an extensive set of diagnostic techniques were used which include schlieren, interferometry, optical streak camera, 4 frames X-ray camera, time resolved X-ray crystal spectrometer, filtered PIN diodes and pinhole camera. Current and voltage probes located at the load area and in the transfer line were used to monitor the electrical parameters. A Nd-YAG laser doubled at 532 nm with a pulse length of 400 ps was used as a light source for schlieren photography and interferometry. Registration of laser probing images with high spatial resolution was done by CCD cameras. To obtain schlieren photographs of plasma evolution in the single discharge the laser pulse was split into four pulses separated by 20 ns.