WIRE NUMBER DOUBLING IN HIGH-WIRE-NUMBER REGIME INCREASES Z-ACCELERATOR X-RAY POWER

Doubling the number of tungsten wires from 120 to 240, keeping the mas s fixed, increased the radiated X-ray power relative to the electrical power at the insulator stack of the Z accelerator by (35 +/- 15)% for 8.75- and 70-mm radii Z-pinch wire arrays. One-dimensional radiation magneto hydrodynamic calculations suggest that the arrays were operati ng in a quasi ''plasma-shell'' regime, where the plasma generated by t he individual wires partially merge prior to the inward implosion of t he entire array.