Wire explosion studies in arrays with small numbers of wires using a range of dischrge parameters

Summary form only given. The initial phase of a wire explosion is important in the entire process of plasma load development in wire array experiments. It is very difficult to understand the behavior of individual wires in multiwire arrays, especially if an array consists of wires made from different materials. Decreasing the number of wires to 2-4 may help to study processes associated with wire explosion and shunting plasma development. Energy deposition and, hence, conditions of wire cores and initial shunting plasma parameters, should strongly depend on circuit and discharge current parameters. There are two limits of interest for the discharge: the voltage regime, when the current through an individual wire is determined by Ohm law and is inversely proportional to its initial resistance; and the current regime, when the current through each wire is determined by the inductance distribution in the load. The current regime is realized if the inductive impedance of the wire exceeds its ohmic resistance. It is obvious that the transition from one regime to the other depends on many parameters, especially the current rise rate through each individual wire. The explosions of individual wires and wire arrays with 2-4 wires have been studied under different discharge conditions using several electrical, optical and X-ray diagnostics. A small generator based on a low inductance capacitor, with a current rise rate of 10-50 A/ns (8 kA maximum current) and the BIN generator with a current rise rate up to 3 kA/ns (270 kA maximum current) were used to drive the wire explosions. It was shown that under some conditions, the initial coronal plasma development does not depend strongly on the wire material