Impact of load variations on the stagnation of nested stainless steel and copper Z pinches

A variety of wire array experiments the last few years at the 20 MA Z Accelerator have been performed to assess the impact of initial load mass, initial load diameter, and variations of the nested array configuration on the K-shell output. Nominally, optimized configurations have been identified, with optimization determined by the highest K-shell output with the fastest rising, narrowest x-ray pulse. In this paper, the results of experiments performed to evaluate additional load configuration variations such as increased radial anode-cathode (RAK) gap, increases in wire number on nested arrays, and orientation of the nested arrays are presented. For stainless steel wire arrays (K-shell emission ∼6.7 keV), increasing the wire number on the nested arrays resulted in increased K-shell yield and K-shell power. Increasing the RAK gap from 6 mm to 10 mm resulted in changes to both the soft x-ray emission and stainless steel K-shell emission. The orientation of the wires on the inner and outer arrays of copper (8.4 keV) wire arrays was not observed to impact the radiated output, although calculations suggest that the effect of wire orientation will be overwhelmed by magnetic field asymmetries induced by the wire location relative to the openings in the return current can.