Development and optimization of an x-pinch radiograph capability for the Z Machine*

X-pinches are pulsed power loads that can be driven by <1 MA of current to make ~micron-scale, <1 ns soft x-ray sources suitable for radiography. Typically, radiography on the Z Machine is performed by irradiating a metal foil with a high-power laser; however radiographs are currently unavailable when shots require the laser for other experimental needs. Thus, we have developed an x-pinch that can fit onto an extended post-hole convolute of the Z Machine's final transmission line stage and uses ~1 MA of the machine's total 20 MA drive. We present results from optimization campaigns on the 1 MA, 100 ns rise Mykonos driver to develop x-pinch radiography sources for point projection (continuum emission) and crystal imaging (k-shell line emission) configurations. Crossed-wire and hybrid x-pinches of Mo or alloys of Co, Cr and Ni were tested at various charge voltages, and x-ray outputs were measured with diodes, spectrometry and penumbral imaging.