X-mode reflectometry for magnetohydrodynamic activity associated with q=1 surface measurements on Tore Supra

Journal Article · Fri Oct 01 00:00:00 EDT 2004 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.1783606· OSTI ID:20636762

Vermare, L; Clairet, F; Gabillet, F; Sabot, R; Sirinelli, A; Heuraux, S; Leclert, G ^[1]

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1. Association Euratom-CEA, CEA/DSM/DRFC/Cadarache, F-13108 Saint-Paul-lez-Durance Cedex (France)

Tore Supra is equipped with two 20 {mu}s fast sweep X-mode reflectometers operating between 50-110 GHz dedicated to density profile determination and an X-mode fixed frequency reflectometer operating between 105-155 GHz for density fluctuation measurements. Heterodyne and sine-cosine detection provide measurements of the reflected signal with high sensitivity. Operating profile reflectometer in burst mode (5 {mu}s dead time between two consecutive sweeps) allows quasi-simultaneous measurements at fixed frequency over a broad frequency band. Thus, information on plasma fluctuations, such as magnetohydrodynamic (MHD) activity, up to 20 kHz as well as a radial localization of the modes is accessible. The temporal evolution of the q=1 rational surface during sawtooth crash activity has been recorded in the plasma center with high spatial resolution. In addition, a direct comparison between signals associated with a central MHD mode from both profile and fluctuation reflectometers, positioned at different toroidal angles, allows one to determine the plasma toroidal velocity.

• OSTI ID: 20636762
• Journal Information: Review of Scientific Instruments, Vol. 75, Issue 10; Other Information: DOI: 10.1063/1.1783606; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DEAD TIME
FLUCTUATIONS
GHZ RANGE 01-100
GHZ RANGE 100-1000
KHZ RANGE 01-100
MAGNETOHYDRODYNAMICS
MODE RATIONAL SURFACES
PLASMA CONFINEMENT
PLASMA DENSITY
PLASMA DIAGNOSTICS
PLASMA INSTABILITY
PLASMA WAVES
SAWTOOTH OSCILLATIONS
SPATIAL RESOLUTION
TORE SUPRA TOKAMAK