Progress in Z-pinch at NINT

Experiments on Z-pinch has been carried out based on a 2 MA pulsed power facility. Gas puff and wire array liners were tested at current 1.4 ∼ 2.1 MA with rise time 80 ∼ 100 ns. For Krypton specific mass of 23 and 47 μg/cm, soft X-ray yield of 55 and 62 kJ, radiation power of 1.9 and 1.7 TW have been obtained, with imploding time of 90 and 118 ns corresponding to current of 1.4 and 1.5 MA and rise time of 80 and 96 ns. For tungsten specific mass of 182 μg/cm, array diameter 12 mm, wire diameter 5 μm, wire number 48 and wire space 0.8 mm, soft X-ray yield of 32 kJ and radiation power of 1.3 TW were obtained with imploding time of 140 ns corresponding to current 1.6 MA and rise time of ∼100 ns. Double nested neon puff liner was tested with keV level X-ray radiation power observed to be greater than that achieved using single liners. 5 filtered XRDs were used to measure X-ray waveform and energy spectrum. A nanosecond, two energy region, 4-framing (for each energy region) soft X-ray imaging camera with 1.8 ns temporal resolution and 1.2 ns timing error was developed to monitor the temporal and spatial evolution of the Z-pinch liner. A nanosecond 4-framing ultraviolet camera was employed to observe the liner's motion during implosion. Total soft X-ray energy was measured by a nickel foil bolometer. Leading (precursor) plasma in the case of tungsten wire array and zip effect in the case of gas puff were observed during implosion. Regarding theoretical approach, driving current waveform will obviously influence initial liner parameter scaling, and maximum imploding kinetic energy per unit liner length can be 0.9 times the square of driving current amplitude multiplying by the natural algorithm of the ratio of initial liner diameter to the final.