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.