skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: COMPLETE SUPPRESSION OF THE m/n=2/1 NEOCLASSICAL TEARING MODE USING RADIALLY LOCALIZED ELECTRON CYCLOTRON CURRENT DRIVE ON DIII-D AND THE REQUIREMENTS FOR ITER

Abstract

OAK-B135 DIII-D experiments demonstrate the first real-time feedback control of the relative location of a narrow beam of microwaves to completely suppress and eliminate a growing tearing mode at the q=2 surface. long wavelength tearing modes such as the m/n = 2/1 instability are particularly deleterious to tokamak operation. Confinement is seriously degraded by the island, plasma rotation can cease (mode-lock) and disruption can occur. The neoclassical tearing mode (NTM) becomes unstable due to the presence of a helically-perturbed bootstrap current and can be stabilized by replacing the missing bootstrap current in the island O-point by precisely located co-electron cyclotron current drive (ECCD). The geometry for the ECCD launch, the second harmonic resonance 2f{sub ce} and the q=2 surface are shown. The optimum position is found when the DIII-D plasma control system (PCS) is put into a search and suppress mode that makes small radial shifts (in about 1 cm steps) in the ECCD location based on minimizing the Mirnov amplitude.

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
GENERAL ATOMICS (US)
Sponsoring Org.:
(US)
OSTI Identifier:
821558
DOE Contract Number:  
AC03-99ER54463
Resource Type:
Conference
Resource Relation:
Conference: IAEA TECHNICAL MEETING ON ECRH PHYSICS AND TECHNOLOGY FOR ITER, KLOSTER-SEEON (DE), 07/14/2003--07/16/2003; Other Information: PBD: 1 Jun 2003
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; BOOTSTRAP CURRENT; CONFINEMENT; CONTROL SYSTEMS; CYCLOTRONS; DOUBLET-3 DEVICE; ELECTRONS; FEEDBACK; GEOMETRY; HARMONICS; IAEA; INSTABILITY; PHYSICS; RESONANCE; ROTATION; WAVELENGTHS

Citation Formats

LA HAYE, RJ, LUCE, TC, PETTY, CC, HUMPHREYS, DA, HYATT, AW, PERKINS, FW, PRATER, R, STRAIT, EJ, and WADE, MR. COMPLETE SUPPRESSION OF THE m/n=2/1 NEOCLASSICAL TEARING MODE USING RADIALLY LOCALIZED ELECTRON CYCLOTRON CURRENT DRIVE ON DIII-D AND THE REQUIREMENTS FOR ITER. United States: N. p., 2003. Web.
LA HAYE, RJ, LUCE, TC, PETTY, CC, HUMPHREYS, DA, HYATT, AW, PERKINS, FW, PRATER, R, STRAIT, EJ, & WADE, MR. COMPLETE SUPPRESSION OF THE m/n=2/1 NEOCLASSICAL TEARING MODE USING RADIALLY LOCALIZED ELECTRON CYCLOTRON CURRENT DRIVE ON DIII-D AND THE REQUIREMENTS FOR ITER. United States.
LA HAYE, RJ, LUCE, TC, PETTY, CC, HUMPHREYS, DA, HYATT, AW, PERKINS, FW, PRATER, R, STRAIT, EJ, and WADE, MR. Sun . "COMPLETE SUPPRESSION OF THE m/n=2/1 NEOCLASSICAL TEARING MODE USING RADIALLY LOCALIZED ELECTRON CYCLOTRON CURRENT DRIVE ON DIII-D AND THE REQUIREMENTS FOR ITER". United States. https://www.osti.gov/servlets/purl/821558.
@article{osti_821558,
title = {COMPLETE SUPPRESSION OF THE m/n=2/1 NEOCLASSICAL TEARING MODE USING RADIALLY LOCALIZED ELECTRON CYCLOTRON CURRENT DRIVE ON DIII-D AND THE REQUIREMENTS FOR ITER},
author = {LA HAYE, RJ and LUCE, TC and PETTY, CC and HUMPHREYS, DA and HYATT, AW and PERKINS, FW and PRATER, R and STRAIT, EJ and WADE, MR},
abstractNote = {OAK-B135 DIII-D experiments demonstrate the first real-time feedback control of the relative location of a narrow beam of microwaves to completely suppress and eliminate a growing tearing mode at the q=2 surface. long wavelength tearing modes such as the m/n = 2/1 instability are particularly deleterious to tokamak operation. Confinement is seriously degraded by the island, plasma rotation can cease (mode-lock) and disruption can occur. The neoclassical tearing mode (NTM) becomes unstable due to the presence of a helically-perturbed bootstrap current and can be stabilized by replacing the missing bootstrap current in the island O-point by precisely located co-electron cyclotron current drive (ECCD). The geometry for the ECCD launch, the second harmonic resonance 2f{sub ce} and the q=2 surface are shown. The optimum position is found when the DIII-D plasma control system (PCS) is put into a search and suppress mode that makes small radial shifts (in about 1 cm steps) in the ECCD location based on minimizing the Mirnov amplitude.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2003},
month = {6}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: