Speaker: William Young (General Fusion): Accurate temperature measurements are critical to establishing the behavior of General Fusion’s SPECTOR plasma injector, both before and during compression. As compression tests impose additional constraints on diagnostic access to the plasma, a two-color, filter-based soft x-ray temperature diagnostic has been implemented. The soft x-ray diagnostic has been validated against a Thomson scattering system on an uncompressed version of SPECTOR with more diagnostic access. The multipoint Thomson scattering diagnostic also provides up to a six point temperature and density profile, with the density measurements validated against a far infrared interferometer. Temperatures above 300 eV have been demonstrated to be sustained for over 500 microseconds in uncompressed plasmas. Optimization of soft x-ray filters is ongoing, in order to balance blocking of impurity line radiation with signal strength.
W. Young, N. Carter, P. Carle, P. O’Shea. Temperature Measurements in Compressed and Uncompressed SPECTOR Plasmas at General Fusion. Exploratory Plasma and Fusion Research Workshop, Vancouver, Canada. August 3, 2017