Observation of ion scale fluctuations in the pedestal region during the edge-localized-mode cycle on the National Spherical Torus Experiment

Diallo, A.; Kramer, G. J.; Bell, R. E.; Guttenfelder, W.; LeBlanc, B. P.; Podesta, M.; Smith, D. R.; McKee, G. J.; Maingi, R.; Fonck, R.

doi:10.1063/1.4773402

Title: Observation of ion scale fluctuations in the pedestal region during the edge-localized-mode cycle on the National Spherical Torus Experiment

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Abstract

Characterization of the spatial structure of turbulence fluctuations during the edge localized mode cycle in the pedestal region is reported. Using the beam emission spectroscopy and the correlation reflectometry systems, measurements show spatial structure-k{sub Up-Tack }{rho}{sub i}{sup ped}-ranging from 0.2 to 0.7 propagating in the ion diamagnetic drift direction at the pedestal top. These propagating spatial scales are found to be anisotropic and consistent with ion-scale microturbulence of the type ion temperature gradient and/or kinetic ballooning modes.

Authors:

Diallo, A.; Kramer, G. J.; Bell, R. E.; Guttenfelder, W.; LeBlanc, B. P.; Podesta, M. ^[1]; Smith, D. R.; McKee, G. J. ^[2]; Maingi, R. ^[3]; Fonck, R. ^[1]

Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States)
Departments of Engineering Physics and Physics, University of Wisconsin, Madison, Wisconsin (United States)
Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831 (United States)

Publication Date:: Tue Jan 15 00:00:00 EST 2013

OSTI Identifier:: 22113351

Resource Type:: Journal Article

Journal Name:: Physics of Plasmas

Additional Journal Information:: Journal Volume: 20; Journal Issue: 1; Other Information: (c) 2013 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ANISOTROPY; BALLOONING INSTABILITY; BOUNDARY LAYERS; CORRELATIONS; EDGE LOCALIZED MODES; ELECTRON TEMPERATURE; EMISSION SPECTROSCOPY; FLUCTUATIONS; ION TEMPERATURE; IONS; PLASMA; TEMPERATURE GRADIENTS; TOKAMAK DEVICES; TURBULENCE

Citation Formats


                    Diallo, A., Kramer, G. J., Bell, R. E., Guttenfelder, W., LeBlanc, B. P., Podesta, M., Smith, D. R., McKee, G. J., Maingi, R., Fonck, R., and Departments of Engineering Physics and Physics, University of Wisconsin, Madison, Wisconsin. Observation of ion scale fluctuations in the pedestal region during the edge-localized-mode cycle on the National Spherical Torus Experiment.  United States: N. p., 2013. 
        Web.  doi:10.1063/1.4773402.

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                    Diallo, A., Kramer, G. J., Bell, R. E., Guttenfelder, W., LeBlanc, B. P., Podesta, M., Smith, D. R., McKee, G. J., Maingi, R., Fonck, R., & Departments of Engineering Physics and Physics, University of Wisconsin, Madison, Wisconsin. Observation of ion scale fluctuations in the pedestal region during the edge-localized-mode cycle on the National Spherical Torus Experiment.  United States.  https://doi.org/10.1063/1.4773402

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                    Diallo, A., Kramer, G. J., Bell, R. E., Guttenfelder, W., LeBlanc, B. P., Podesta, M., Smith, D. R., McKee, G. J., Maingi, R., Fonck, R., and Departments of Engineering Physics and Physics, University of Wisconsin, Madison, Wisconsin. 2013.  
        "Observation of ion scale fluctuations in the pedestal region during the edge-localized-mode cycle on the National Spherical Torus Experiment".  United States.  https://doi.org/10.1063/1.4773402.

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@article{osti_22113351,

  title        = {Observation of ion scale fluctuations in the pedestal region during the edge-localized-mode cycle on the National Spherical Torus Experiment},

  author       = {Diallo, A. and Kramer, G. J. and Bell, R. E. and Guttenfelder, W. and LeBlanc, B. P. and Podesta, M. and Smith, D. R. and McKee, G. J. and Maingi, R. and Fonck, R. and Departments of Engineering Physics and Physics, University of Wisconsin, Madison, Wisconsin},

  abstractNote = {Characterization of the spatial structure of turbulence fluctuations during the edge localized mode cycle in the pedestal region is reported. Using the beam emission spectroscopy and the correlation reflectometry systems, measurements show spatial structure-k{sub Up-Tack }{rho}{sub i}{sup ped}-ranging from 0.2 to 0.7 propagating in the ion diamagnetic drift direction at the pedestal top. These propagating spatial scales are found to be anisotropic and consistent with ion-scale microturbulence of the type ion temperature gradient and/or kinetic ballooning modes.},

  doi          = {10.1063/1.4773402},

  url          = {https://www.osti.gov/biblio/22113351},
  journal      = {Physics of Plasmas},

  issn         = {1070-664X},

  number       = 1,

  volume       = 20,

  place        = {United States},

  year         = {Tue Jan 15 00:00:00 EST 2013},

  month        = {Tue Jan 15 00:00:00 EST 2013}

}

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