Wire number dependence of the implosion dynamics, stagnation and radiation output of tungsten wire arrays at Z

We report results of the experimental campaign which studied the initiation, implosion dynamics and radiation yield of tungsten wire arrays as a function of the wire number. The wire array dimensions and mass were those of interest for the Z-pinch driven ICF program. An optimization study of the X-ray emitted peak power, rise time and FWHM was effectuated by varying the wire number while keeping the total array mass constant and equal to ~5.8 mg. The driver utilized is the ~20 MA Z accelerator in its usual short pulse mode of 100 ns. We studied single arrays of 20 mm diameter and 1 cm height. The smaller wire number studied was 30 and the largest 600. It appears that 600 is the highest achievable wire number with present day's technology. Radial and axial diagnostics were utilized including crystal monochromatic X-ray backlighter. An optimum wire number of ~370 was observed which is very close to the routinely utilized 300 for the ICF program in Sandia.