Using tamped exploding wires to generate strongly coupled plasmas

Plasmas become strongly coupled (SCP) when the coulomb interaction energy between particles is comparable or greater than the thermal kinetic energy. This occurs at low temperatures (T ∼ 1 eV) and high densities (n_c- ∼10²¹ cm^-3). SCPs are found in the interior of gas planets and white dwarf stars, as well as in high energy density physics experiments. We present a pulsed power and plasma shaping system designed to generate an aluminum SCP with a rectangular column profile. A 3.5 kJ, 4-stage Marx has been constructed to explode 200-micron aluminum wires fused in lead glass (p ∼ 5.4 g/cm³). The glass tamper restricts the exploding wires radial expansion, while axial expansion is permitted. The central region of the expanding plasma passes through a 100-micron square aperture assembly creating a plasma column. Above the aperture, the plasma plume is expected to have a density of one-tenth solid (∼ 0.27 g/cm³) and a temperature of the order 1 eV. Absorption of magnesium K-shell x-rays from a laser-produced backlighter is used to measure the density of the plasma. An optical pyrometer is used to estimate the plasma surface temperature based on a blackbody approximation with constant emissivity. Raven and Crunch were used to simulate the behaviour inside the tamped region using conductivity tables generated by Desjarlais. The simulations predict fairly uniform density and temperature conditions in the central 100-microns of the tamped exploding wire. The plasma plume above the aperture will be used for equation of state studies of SCP matter.