Ablation dynamics of a single wire with closely coupled return current

Summary form only given. Studies of ablation rates in wire arrays show a strong correlation between ablation rate and global magnetic field. However, ablation rate measurements are rather complicated for cylindrical wire arrays due to their 3-D geometry and potentially uneven current distribution. By using a single wire with a closely placed return current conductor we are able to obtain straightforward measurements of ablation rate. The closely placed return current conductor should create a strong enough "global" magnetic field to achieve ablation rates similar to those seen with wire array experiments. This relatively simple geometry allows straightforward direct observation of coronal plasma flow with a laser interferometer and material density measurements to be made in and around the core with an X-pinch backlighter. These experiments, carried out on Cornell\´s 400 kA, 50 ns rise time pulsed power machine, will allow us to determine how the ablation rate scales with global magnetic field (current), wire diameter, and wire material. Furthermore, these measurements could be used to benchmark computer simulations. In addition, experiments on Imperial College\´s Magpie pulsed power machine have shown a quasi-periodic modulation of the plasma as it flows from the wire cores in cylindrical arrays. We hope to observe a similar periodic structure and its dependence on wire material, again in a simpler geometry than the cylindrical array.