Measurements of Early-Time Plasma Evolution in the Hawk Dense Plasma Focus

The 650 kA Hawk pulsed power generator at NRL has been configured as a fast (1.2 μs), high in ductance (607 nH) driver for a dense plasma focus load. The current pulse is initiated in a radially injected deuterium plasma. This plasma is accelerated through a coaxial region, and pinches onto neutral deuterium injected axially by a gas-puff valve. A ribbon beam interferometer is used to diagnose the plasma in the coaxial region at several radii, providing time resolved electron density measurements through the initiation and axial run-down phases of the implosion. We present interferometry results alongside imaging, spectroscopic, electrical, and radiation measurements that track the evolution of the imploding current sheath.