Speaker
Description
The Z-machine housed at Sandia National Laboratories is instrumental in plasma physics research across a range of applications. University-scale z-pinch experiments, such as gas-puff z-pinches, can inform the high-value experiments conducted at Sandia. A gas puff z-pinch requires gas to be puffed into the region between two electrodes, which is then pulsed with a high voltage [1]. The gas is ionized and compressed as the current flows across the electrodes, allowing for a systematic study of pinch phenomena. It involves a rapid plasma acceleration and compression resulting in fusion reactions [2]. These are largely the result of micro-pinch instabilities, which are regions of extreme pressures and temperatures within the plasma and are poorly understood. We report on the progress made in developing this system for MAIZE.
Additionally, we have revamped switch diagnostics on MAIZE, which consists of a set of 40 capacitor-switch-capacitor “bricks”. Discharging these capacitors is carried out by the breakdown of the spark-gap switch, resulting in the emission of light. Monitoring this light provides information on switch performance– whether a switch fired early or synchronously with the other switches. Examination of 40 switches during each shot with a dedicated photomultiplier tube (PMT) and oscilloscope channel is a resource-intensive process. A circuit can be set up that reduces a PMT to a computer bit and with such a circuit, six PMTs can uniquely identify a single pre-firing switch out of 40.
- J. Giuliani, “A Review of the Gas-Puff Z-Pinch as an X-Ray and Neutron Source”, IEEE Trans. Plasma Sci. 43, 2385 (2015).
- M. Krishnan, “The Dense Plasma Focus: A Versatile Dense Pinch for Diverse Applications”, IEEE Trans. Plasma Sci. 40, 3189 (2012).
*Work supported by a seed grant from the Michigan Memorial Phoenix Project and the NNSA Stewardship Sciences Academic Programs under DOE Cooperative Agreement DE-NA0003764.
