Autocorrelation and crossed‐sightline correlation of ECE for measurement of electron temperature and density fluctuations on ATF and TEXT

The great stumbling block in the quest for fusion power using magnetic confinement devices is anomalous transport. It is conjectured that turbulent plasma fluctuations may be responsible for the degraded energy confinement observed in experiments. There exists a clear need for more detailed experimental studies of plasma microturbulence. A conceptual design is presented for a diagnostic to measure electron temperature and density fluctuations using electron cyclotron emission (ECE). The proposed ECE systems will employ autocorrelation and cross‐correlation techniques to measure radiation from the Advanced Toroidal Facility (ATF) at Oak Ridge National Laboratory (ORNL) and also from the Texas Experimental Tokamak (TEXT) at the University of Texas. This set of experiments on a stellarator and a tokamak will allow a unique comparative study of the fluctuation physics in the two different magnetic configurations. This article presents the theoretical basis and conceptual design of the diagnostic.