X-Ray Emission From a Tabletop $X$-Pinch Device

Based on a compact (2 m × 1 m × 1.5 m) pulsed-current generator (~100 kA and 60 ns), a tabletop X-pinch device was constructed and tested. The load current was almost unchanged for X-pinches made using different wires (5-, 8-, 10-, and 13-μm W wires and 13- and 25-μm Mo wires), which means that the impedance of the wires is much lower than the total impedance of the load section. When the aforementioned wires were used as a two-wire load, X-ray pulses from the X-pinch were always observed. As the mass of the two-wire load increases, the time delay of the X-ray emission relative to the beginning of the load current increases. As was expected, the X-ray pulse consists of a single peak or two overlapping peaks of subnanosecond pulsewidth. The X-ray source is usually one point or two partly overlapping points, which is consistent with the measurement of an X-ray pulse. The size of the X-ray point source ranges from 5 to 50 μm. Two X-ray pulses with a time interval on the order of 10 ns were often observed for a small-mass load when the load current is high enough. The appearance of the second X-ray pulse is attributed to the second pinch of the plasma.