Spectroscopic Measurements of Plasmas in the Power Flow Regions on the Z Machine

Pulsed power devices depend on the ability to deliver high voltages and currents to a variety of complex loads with minimal transmission losses. The Z Machine at Sandia National Laboratories can deliver up to 26MA within a few 10’s of nanoseconds to multiple z-pinch type loads. An effort is underway to measure plasma parameters such as temperatures and densities within the power flow regions on the Z Machine. A proper physics understanding of efficient high current delivery is necessary to ensure that higher current devices such as Z-Next will perform as designed. In the power flow regions, plasmas form on the electrode surfaces and propagate into the vacuum gap, providing a current loss mechanism. These plasmas are measured spectroscopically using a 1m Czerny-Turner spectrometer with a fast (nanosecond) streak camera output. Data is analyzed using detailed, time-dependent, collisional-radiative (CR) and radiation transport modeling. Recent results will be presented.