Effect of a Pulsed Magnetic Mirror on Wire-array Z-pinch

Axial magnetic field has been shown to increase fusion yield in a variety of inertial confinement fusion experiments. In these experiments, a spatially and temporally uniform magnetic field is applied to the fusion plasma to reduce electron thermal conduction and increase alpha particle energy deposition. We hypothesized that a pulsed magnetic mirror could potentially provide axial end-plugging, increasing peak plasma density and temperature, in addition to the benefits of static uniform magnetic field. We developed an auto-magnetizing wire-array platform to study the effect of a pulsed magnetic mirror on wire-array Z-pinch plasma. The wire-array are threaded through twisted tube electrodes which provide helical conduction paths. As the current driving the Z-pinch passes through the wire-array, an axial magnetic field is generated simultaneously, and the field strength increases and decreases with the current pulse. By using different combinations of twists in the tube electrodes and in the wire-array, we could create different axial field profile with different mirror ratio and field strength. Reduction in axial outflow and rotation of the precursor plasma on wire-array axis are observed in mirror configurations. We will present the effect of mirror ratio and axial field strength on precursor plasma temperature and overall X-ray output. 3D MHD simulations of the experiments using PERSEUS will also be presented.