TEMPERATURE-FLUCTUATION MEASUREMENTS WITH ECE ON W7-AS

Electron temperature fluctuations at a relative level of the order of 0.1% in the presence of strong inherent intensity fluctuations of ther mal radiation can be measured applying correlation radiometry of elect ron cyclotron emission. The diagnostic problem and the technique are b riefly reviewed. Examples are given which characterize the temperature fluctuations as measured in the core region of purely ECRH heated pla smas with respect to spectrum, relative level, and coherence length. P arameter dependences are discussed.