7th International Reflectometry Workshop for Fusion Plasma Diagnostics, 9-12 de Maio de 2005, Garching, Alemanha

	Radial Behaviour of Density Fluctuations Deduced from FM-CW Tore Supra Reflectometry Data
	S. Heuraux, L. Vermare, F. Clairet, G. Leclert e F. da Silva
	Resumo
	On Tore Supra, FM-CW X-mode Reflectometry provides electron density profile routinely and automatically on the shot to shot basis [1]. It can provide, as well, localised information on the plasma fluctuations. Up to now the fixed frequency reflectometer was used to give good relative evolution and quantitative information if the local characteristic length of the fluctuations is known in the vicinity of the cut-off layer [2-3], as the refractive index gradient length, and assuming the corresponding wavelength can be associated to an oscillation of the cut-off. We explore here the possibility to obtain quantitative information about the radial evolution of the density fluctuation, either plasma turbulence, deduced from the wavenumber spectrum (kf-spectrum) of the density fluctuation based on the analysis of the phase fluctuation of the reflected signal obtained during fast frequency sweeps [4].