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Title: Physics of internal transport barrier of toroidal helical plasmas

Abstract

The role of zonal flows (ZFs) in the formation of an internal transport barrier in a toroidal helical plasma is analyzed. The turbulent transport coefficient is shown to be suppressed when the plasma state changes from the branch of a weak negative radial electric field to the strong positive one. This new transition of turbulent transport is caused by the change of the damping rate of the ZFs. It is clearly demonstrated, theoretically and experimentally, that the damping rate of the ZFs governs the global confinement of toroidal plasmas.

Authors:
; ; ; ; ; ; ;  [1];  [2];  [2];  [3];  [2]
  1. National Institute for Fusion Science, Toki 509-5292 (Japan)
  2. (Japan)
  3. (United States)
Publication Date:
OSTI Identifier:
20974815
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 2; Other Information: DOI: 10.1063/1.2435310; (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; DAMPING; ELECTRIC FIELDS; PLASMA; PLASMA CONFINEMENT; STELLARATORS; TURBULENCE

Citation Formats

Itoh, K., Toda, S., Fujisawa, A., Itoh, S.-I., Yagi, M., Fukuyama, A., Diamond, P. H., Ida, K., Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Department of Nuclear Engineering, Kyoto University, Kyoto, 606-8501, Department of Physics, University of California, San Diego, San Diego, California 92093-0319, and National Institute for Fusion Science, Toki 509-5292. Physics of internal transport barrier of toroidal helical plasmas. United States: N. p., 2007. Web. doi:10.1063/1.2435310.
Itoh, K., Toda, S., Fujisawa, A., Itoh, S.-I., Yagi, M., Fukuyama, A., Diamond, P. H., Ida, K., Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Department of Nuclear Engineering, Kyoto University, Kyoto, 606-8501, Department of Physics, University of California, San Diego, San Diego, California 92093-0319, & National Institute for Fusion Science, Toki 509-5292. Physics of internal transport barrier of toroidal helical plasmas. United States. doi:10.1063/1.2435310.
Itoh, K., Toda, S., Fujisawa, A., Itoh, S.-I., Yagi, M., Fukuyama, A., Diamond, P. H., Ida, K., Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Department of Nuclear Engineering, Kyoto University, Kyoto, 606-8501, Department of Physics, University of California, San Diego, San Diego, California 92093-0319, and National Institute for Fusion Science, Toki 509-5292. Thu . "Physics of internal transport barrier of toroidal helical plasmas". United States. doi:10.1063/1.2435310.
@article{osti_20974815,
title = {Physics of internal transport barrier of toroidal helical plasmas},
author = {Itoh, K. and Toda, S. and Fujisawa, A. and Itoh, S.-I. and Yagi, M. and Fukuyama, A. and Diamond, P. H. and Ida, K. and Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580 and Department of Nuclear Engineering, Kyoto University, Kyoto, 606-8501 and Department of Physics, University of California, San Diego, San Diego, California 92093-0319 and National Institute for Fusion Science, Toki 509-5292},
abstractNote = {The role of zonal flows (ZFs) in the formation of an internal transport barrier in a toroidal helical plasma is analyzed. The turbulent transport coefficient is shown to be suppressed when the plasma state changes from the branch of a weak negative radial electric field to the strong positive one. This new transition of turbulent transport is caused by the change of the damping rate of the ZFs. It is clearly demonstrated, theoretically and experimentally, that the damping rate of the ZFs governs the global confinement of toroidal plasmas.},
doi = {10.1063/1.2435310},
journal = {Physics of Plasmas},
number = 2,
volume = 14,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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