Turbulent temperature fluctuations are measured on the ASDEX Upgrade tokamak using pairs of closely spaced, narrow-band heterodyne radiometer channels and a standard correlation technique. The pre-detection spacing and bandwidth of the radiometer channel pairs is chosen such that they are physically separated less than a turbulent correlation length, but do not overlap. The radiometer has 4 fixed filter frequency channels and two tunable filter channels for added flexibility in the measurement position. Relative temperature fluctuation amplitudes are observed in a helium plasma to be δT/T = (0.76 ± 0.02)%, (0.67 ± 0.02)%, and (0.59 ± 0.03)% at normalised toroidal flux radius of ρtor = 0.82, 0.75, and 0.68, respectively.
|Journal||Review of Scientific Instruments|
|Publication status||Published - 1 Nov 2016|
|Event||43rd European Physical Society Conference on Plasma Physics, EPS 2016 - Leuven, Belgium|
Duration: 4 Jul 2016 → 8 Jul 2016
Conference number: 43