Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak

Garofalo, A M; Burrell, K H; DeBoo, J C; DeGrassie, J S; Jackson, G L; Schaffer, M J; Strait, E J; Lanctot, M; Reimerdes, H; Solomon, W M

doi:10.1103/PHYSREVLETT.101.195005

Title: Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak

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Abstract

We present the first evidence for the existence of a neoclassical toroidal rotation driven in a direction counter to the plasma current by nonaxisymmetric, nonresonant magnetic fields. At high beta and with large injected neutral beam momentum, the nonresonant field torque slows down the plasma toward the neoclassical 'offset' rotation rate. With small injected neutral beam momentum, the toroidal rotation is accelerated toward the offset rotation, with resulting improvement in the global energy confinement time. The observed magnitude, direction, and radial profile of the offset rotation are consistent with neoclassical theory predictions [A. J. Cole et al., Phys. Rev. Lett. 99, 065001 (2007)].

Authors:

Garofalo, A M; Burrell, K H; DeBoo, J C; DeGrassie, J S; Jackson, G L; Schaffer, M J; Strait, E J ^[1]; Lanctot, M; Reimerdes, H ^[2]; Solomon, W M ^[3]

General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)
Columbia University, 2960 Broadway, New York, New York 10027-1754 (United States)
Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 08543-0451 (United States)

Publication Date:: Fri Nov 07 00:00:00 EST 2008

OSTI Identifier:: 21179898

Resource Type:: Journal Article

Journal Name:: Physical Review Letters

Additional Journal Information:: Journal Volume: 101; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevLett.101.195005; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0031-9007

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CONFINEMENT TIME; ELECTRIC CURRENTS; HIGH-BETA PLASMA; MAGNETIC FIELDS; NEOCLASSICAL TRANSPORT THEORY; ROTATION; TOKAMAK DEVICES

Citation Formats


                    Garofalo, A M, Burrell, K H, DeBoo, J C, DeGrassie, J S, Jackson, G L, Schaffer, M J, Strait, E J, Lanctot, M, Reimerdes, H, and Solomon, W M. Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak.  United States: N. p., 2008. 
        Web.  doi:10.1103/PHYSREVLETT.101.195005.

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                    Garofalo, A M, Burrell, K H, DeBoo, J C, DeGrassie, J S, Jackson, G L, Schaffer, M J, Strait, E J, Lanctot, M, Reimerdes, H, & Solomon, W M. Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak.  United States.  https://doi.org/10.1103/PHYSREVLETT.101.195005

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                    Garofalo, A M, Burrell, K H, DeBoo, J C, DeGrassie, J S, Jackson, G L, Schaffer, M J, Strait, E J, Lanctot, M, Reimerdes, H, and Solomon, W M. 2008.  
        "Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak".  United States.  https://doi.org/10.1103/PHYSREVLETT.101.195005.

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@article{osti_21179898,

  title        = {Observation of Plasma Rotation Driven by Static Nonaxisymmetric Magnetic Fields in a Tokamak},

  author       = {Garofalo, A M and Burrell, K H and DeBoo, J C and DeGrassie, J S and Jackson, G L and Schaffer, M J and Strait, E J and Lanctot, M and Reimerdes, H and Solomon, W M},

  abstractNote = {We present the first evidence for the existence of a neoclassical toroidal rotation driven in a direction counter to the plasma current by nonaxisymmetric, nonresonant magnetic fields. At high beta and with large injected neutral beam momentum, the nonresonant field torque slows down the plasma toward the neoclassical 'offset' rotation rate. With small injected neutral beam momentum, the toroidal rotation is accelerated toward the offset rotation, with resulting improvement in the global energy confinement time. The observed magnitude, direction, and radial profile of the offset rotation are consistent with neoclassical theory predictions [A. J. Cole et al., Phys. Rev. Lett. 99, 065001 (2007)].},

  doi          = {10.1103/PHYSREVLETT.101.195005},

  url          = {https://www.osti.gov/biblio/21179898},
  journal      = {Physical Review Letters},

  issn         = {0031-9007},

  number       = 19,

  volume       = 101,

  place        = {United States},

  year         = {Fri Nov 07 00:00:00 EST 2008},

  month        = {Fri Nov 07 00:00:00 EST 2008}

}

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