Analytical analysis of the ablation phase of low number wire arrays

Summary form only given. Whilst the dynamical evolution of wire arrays is well understood, and multi-dimensional Magneto-Hydrodynamic (MHD) modeling has demonstrated significant progress, a comprehensive predictive capability has not been realized to date. Recent experimental investigations have highlighted the need to more closely examine the ablation structure and its dependence on the initial parameters of the array. In particular, the range over which the ablated plasma is accelerated, and hence extent to which magnetic flux is convected into the array, is often a disputed point in the comparison simulation and analytical work. Recent work at UC San Diego [ 1 ] uses a modification of the Lebedev rocket model of wire ablation to fit the range of ablation velocities which are observed in experiments. This analysis can be extended to infer the 2D distribution of effective velocities which redistribute the mass as a function of time. From this data it may be possible to direct observe the acceleration region in a wire array. An analysis of the effect of array geometry on the determined acceleration region will be attempted using interferographic and radiographic data from experiments at 200 kA to 1 MA. Conclusions and possible extensions to this work will be presented and discussed.