Semi-empirical modeling of exploding wire plasma in water for study on strongly coupled plasma

Pulsed wire discharges are utilized for study on high energy density physics. A pulse power generator composed of a water-filled test chamber, a low inductance discharge section and a cylindrically arranged capacitor bank, is used to explode thin wires. A variety of thin wires made of copper or aluminum are exploded at the central axis in the test chamber. The electrical energy powered into the plasma is estimated by integration of voltage-current characteristics of the pulsed discharge. In order to estimate the plasma density, the boundary of the plasma evolution is observed with a fast framing photography. The cylindrical shock wave in water is measured by the schlieren method and the history of pressure evolution is evaluated by comparing the shock wave trajectory with numerical estimation based on a quotidian equation of state (QEOS). Evolutions of electrical conductivity, corresponding coupling parameters and the equation of state of the plasma are discussed based on the experimentally obtained plasma evolution.