Double and single planar wire arrays at high and low impedance university-scale generators
Résumé
Single Planar Wire Arrays (SPWA) and Double Planar Wire Arrays (DPWA), which consist of one or two parallel rows of wires, respectively, have demonstrated high radiation efficiency (up to 30 kJ), compact size (1.5-3 mm), and usefulness for various applications in experiments on the high-impedance Zebra (1.9Ω, 1 MA, 100 ns). For example, DPWAs are very suitable for the new compact multi-source hohlraum concept, astrophysical applications, and as an excellent radiation source. Their implosion dynamics strongly depends on the critical load parameter, the aspect ratio Φ (width to inter-planar gap Δ) as well as on load wire material and mass. We have studied implosion dynamics and radiative properties of DPWAs at the enhanced Zebra current of 1.5-1.7 MA and have demonstrated the new regimes of implosions with asymmetric jets, no precursor formation, and very early radiation for larger sized (Δ=9 mm, Φ=0.54) and precursor formation and strong cold Ka emission for standard sized (Δ=6 mm, Φ=1.28) DPWAs.