Development progress of Correlation ECE and n-T cross-phase angle diagnostics for ASDEX-Upgrade
POSTER
Abstract
Relative turbulent temperature fluctuation amplitudes can be measured using Correlation ECE (CECE). This technique uses two narrow frequency-band radiometer channels, with an equivalent physical spacing within a turbulent radial correlation length. Correlation techniques select the common turbulent fluctuation while suppressing uncorrelated thermal noise. If such a diagnostic views the same part of the plasma as a reflectometer, then the coherence and cross-phase angle between temperature and density fluctuations can be measured. Two 2nd harmonic, X-mode, CECE radiometers have recently been installed on ASDEX Upgrade, one of which shares the quasi-optical steerable antenna of an existing Doppler reflectometer, i.e with a common line of sight of the plasma. We report on the progress of the installation and preliminary data from both systems.