$X$-Pinch Experiments on 1-MA “QiangGuang-1” Facility

The results of an experimental investigation of $X$-pinch performance on the 1-MA “QiangGuang-1” facility are presented. “QiangGuang-1” is a linear-transformer-driver-based low-impedance pulsed power machine which provides a peak current of 0.9–1.3 MA and a 10%–90% rise time of 50–60 ns. $X$-pinch loads with 2–32 wires of different wire materials (Al, W, and Mo) with wire diameters from 25 to 100 $ \mu\hbox{m}$ have been tested. The number and size of bright spots, timing of the first X-ray burst, $X$-pinch dynamics, and X-ray spectroscopy have been studied using a set of diagnostics with spatial and/or temporal resolution. A single bright spot obtained from a $30 \times 25\ \mu\hbox{m}$ W $X$ -pinch produced 42 J (35 GW) in the 1–10-keV energy range. The smallest bright spot size (radiating $> 1.2$ keV) observed was about 70 $\mu\hbox{m}$. Linear relations between the timing of the first X-ray burst and the wire parameters (diameter and number) in W $X$-pinches were observed. A spatially large extreme ultraviolet plasma radiation region at the crossing point was typically observed. Al $X$-pinch plasma parameters were estimated from X-ray spectroscopy.