Optical Spectroscopic Measurements of the Z Machine Power Flow Region

Pulsed power machines typically utilize vacuum transmission lines to deliver energy to the load. Large-scale drivers often employ several parallel transmission lines to reduce inductance. Post-hole convolutes can be used to combine the current from the transmission lines at the load. Losses in the post-hole convolute and vacuum transmission lines on the Z-machine are as high as 20{\%} of the peak current. Spectroscopic measurements of the plasma that forms on the power flow surfaces are underway. A second visible spectroscopy system has been added to the Z diagnostic suite, which allows symmetry measurements of the plasma formation. Investigations of the convolute plasma origin and propagation are ongoing. *Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.