Axially Correlated Ablation Between Neighboring Wires in a Z-Pinch

Summary form only given. Wire array experiments utilizing four pair of 7.5 micron diameter tungsten wires spaced 244 nm apart were performed using the COBRA accelerator at Cornell University during a collaboration between Cornell University and the University of Michigan. The wire array load was driven with a 1 MV, 1 MA, 100 ns rise-time pulse; molybdenum x-pinches in the return current path were used as x-ray backlighters to image the wire cores approximately 65 ns into the current pulse. These images suggested axially correlated inward and outward displacements between paired wires. In addition, the outwardly displaced correlated region was more severely ablated than the rest of the axial positions in the wire-pair. A subsequent shot series was performed on COBRA to reproduce this possible correlation effect. As of January 2007, a total of nine wire-pair images were obtained; preliminary analysis indicated axial correlation in four of these wire-pairs. A more detailed analysis is underway to quantify the observed correlated displacement and ablation regions, as well as to identify physical mechanisms for this observed phenomenon.