Experimental Analysis of the Acceleration Region in Tungsten Wire Arrays

We present the first analysis of the ablated plasma flow acceleration region in tungsten cylindrical wire arrays within 1 mm of the wire core. We apply a recently developed modification to the Lebedev rocket model to infer the 2-D distribution of effective velocities which redistribute the array mass as a function of time. From these data, it is possible to directly observe the acceleration region in a wire array. Analysis of radiography data from the 1-MA Cornell Beam Research Accelerator machine suggests a region of rapid acceleration extending up to 300 μm from the wire core in 16 wire tungsten arrays.