Analysis of anomalous resistivity during the conduction phase of the plasma erosion opening switch: Interim report

During the conduction phase of the plasma erosion opening switch, the current channel width in the body of the plasma away from the electrodes has been observed to be many times wider than the collisionless skin depth. Anomalous collisions have been invoked to explain this discrepancy. Here the problem is analyzed using an electrostatic Vlasov approach and an unstable ion acoustic mode is identified. The derived growth rate is fast enough and the nonlinear saturation level is high enough to explain the observed magnetic field penetration. 21 refs., 3 figs