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Title: Fast-wave multifrequency diagnostic of tokamak plasmas

Abstract

An exploratory investigation, both computational and experimental, is made of the diagnostic possibilities of a fast wave-based method for measuring the ion density and temperature profiles of tokamak plasmas. The concept consists of simultaneously launching several discrete frequencies and detecting their amplitude and phase at various toroidal locations. This study focuses on an array of frequencies that match the second harmonic of the ion gyrofrequency at various radial locations in the plasma profile. The method is explored with simple, wave-propagation codes for parameters corresponding to the Electric Tokamak (ET) [R. J. Taylor, et al., Nucl. Fusion 42, 46 (2002)] and ITER [R. Aymar, P. Barabaschi, and Y. Shimomura, Plasma Phys. Controlled Fusion 44, 519 (2002)]. An experimental investigation of the concept has been performed in a large tokamak (ET) in which six frequencies are launched and detected at four toroidal locations. Positive results obtained indicate that the concept and other variants deserve to be pursued in greater depth, using more sophisticated codes.

Authors:
; ;  [1]
  1. Physics and Astronomy Department, University of California, Los Angeles, Los Angeles, California 90095 (United States)
Publication Date:
OSTI Identifier:
20974991
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 5; Other Information: DOI: 10.1063/1.2734189; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AMPLITUDES; ELECTROMAGNETIC RADIATION; ELECTRON TEMPERATURE; GYROFREQUENCY; ION DENSITY; ION TEMPERATURE; IONS; ITER TOKAMAK; PLASMA; PLASMA CONFINEMENT; PLASMA DENSITY; PLASMA DIAGNOSTICS; PLASMA RADIAL PROFILES; WAVE PROPAGATION

Citation Formats

LaFonteese, D. J., Morales, G. J., and Taylor, R. J.. Fast-wave multifrequency diagnostic of tokamak plasmas. United States: N. p., 2007. Web. doi:10.1063/1.2734189.
LaFonteese, D. J., Morales, G. J., & Taylor, R. J.. Fast-wave multifrequency diagnostic of tokamak plasmas. United States. doi:10.1063/1.2734189.
LaFonteese, D. J., Morales, G. J., and Taylor, R. J.. Tue . "Fast-wave multifrequency diagnostic of tokamak plasmas". United States. doi:10.1063/1.2734189.
@article{osti_20974991,
title = {Fast-wave multifrequency diagnostic of tokamak plasmas},
author = {LaFonteese, D. J. and Morales, G. J. and Taylor, R. J.},
abstractNote = {An exploratory investigation, both computational and experimental, is made of the diagnostic possibilities of a fast wave-based method for measuring the ion density and temperature profiles of tokamak plasmas. The concept consists of simultaneously launching several discrete frequencies and detecting their amplitude and phase at various toroidal locations. This study focuses on an array of frequencies that match the second harmonic of the ion gyrofrequency at various radial locations in the plasma profile. The method is explored with simple, wave-propagation codes for parameters corresponding to the Electric Tokamak (ET) [R. J. Taylor, et al., Nucl. Fusion 42, 46 (2002)] and ITER [R. Aymar, P. Barabaschi, and Y. Shimomura, Plasma Phys. Controlled Fusion 44, 519 (2002)]. An experimental investigation of the concept has been performed in a large tokamak (ET) in which six frequencies are launched and detected at four toroidal locations. Positive results obtained indicate that the concept and other variants deserve to be pursued in greater depth, using more sophisticated codes.},
doi = {10.1063/1.2734189},
journal = {Physics of Plasmas},
number = 5,
volume = 14,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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  • No abstract prepared.
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