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

Vermare, L; Clairet, F; Gabillet, F; Sabot, R; Sirinelli, A; Heuraux, S; Leclert, G

doi:10.1063/1.1783606

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

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Abstract

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.

Authors:

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

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

Publication Date:: Fri Oct 01 00:00:00 EDT 2004

OSTI Identifier:: 20636762

Resource Type:: Journal Article

Journal Name:: Review of Scientific Instruments

Additional Journal Information:: Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1063/1.1783606; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0034-6748

Country of Publication:: United States

Language:: English

Subject:: 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

Citation Formats


                    Vermare, L, Clairet, F, Gabillet, F, Sabot, R, Sirinelli, A, Heuraux, S, Leclert, G, LPMI, CNRS 7040, Univ. Henri Poincare Nancy I, BP239 54506 Vandoeuvre Cedex, and PIIM, UMR 6633 CNRS, Univ. de Provence, Faculte de St Jerome case 321, 13397 Marseille Cedex 20. X-mode reflectometry for magnetohydrodynamic activity associated with q=1 surface measurements on Tore Supra.  United States: N. p., 2004. 
        Web.  doi:10.1063/1.1783606.

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                    Vermare, L, Clairet, F, Gabillet, F, Sabot, R, Sirinelli, A, Heuraux, S, Leclert, G, LPMI, CNRS 7040, Univ. Henri Poincare Nancy I, BP239 54506 Vandoeuvre Cedex, & PIIM, UMR 6633 CNRS, Univ. de Provence, Faculte de St Jerome case 321, 13397 Marseille Cedex 20. X-mode reflectometry for magnetohydrodynamic activity associated with q=1 surface measurements on Tore Supra.  United States.  https://doi.org/10.1063/1.1783606

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                    Vermare, L, Clairet, F, Gabillet, F, Sabot, R, Sirinelli, A, Heuraux, S, Leclert, G, LPMI, CNRS 7040, Univ. Henri Poincare Nancy I, BP239 54506 Vandoeuvre Cedex, and PIIM, UMR 6633 CNRS, Univ. de Provence, Faculte de St Jerome case 321, 13397 Marseille Cedex 20. 2004.  
        "X-mode reflectometry for magnetohydrodynamic activity associated with q=1 surface measurements on Tore Supra".  United States.  https://doi.org/10.1063/1.1783606.

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@article{osti_20636762,

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

  author       = {Vermare, L and Clairet, F and Gabillet, F and Sabot, R and Sirinelli, A and Heuraux, S and Leclert, G and LPMI, CNRS 7040, Univ. Henri Poincare Nancy I, BP239 54506 Vandoeuvre Cedex and PIIM, UMR 6633 CNRS, Univ. de Provence, Faculte de St Jerome case 321, 13397 Marseille Cedex 20},

  abstractNote = {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.},

  doi          = {10.1063/1.1783606},

  url          = {https://www.osti.gov/biblio/20636762},
  journal      = {Review of Scientific Instruments},

  issn         = {0034-6748},

  number       = 10,

  volume       = 75,

  place        = {United States},

  year         = {Fri Oct 01 00:00:00 EDT 2004},

  month        = {Fri Oct 01 00:00:00 EDT 2004}

}

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