Reflectometry experiment on the tokamak TORE-SUPRA

Reflectometry experiments on TORE-SUPRA is designed to measure routinely the electron density profile of the plasma and to follow all change in the gradient. Broadband technique is used, and, the frequency range is 25-75 GHz for the O mode allowing us to measure densities between 8.5 10-8 and 6.8. 10-19 m-3. X mode technique is under development with a frequency range of 75-110 GHz. It will be used for the determination of the density near the scrape-off layer according to previous experiments and, fixed frequency measurements for fluctuation studies. After a brief theoretical recall, an overview of the experimental set-up, detection technique, and signal analysis method is given, followed by some experimental results. 7 figs