Zonal flows and long-distance correlations during the formation of the edge shear layer in the TJ-II stellarator

@article{Calvo2009ZonalFA,
  title={Zonal flows and long-distance correlations during the formation of the edge shear layer in the TJ-II stellarator},
  author={Iv{\'a}n Calvo and Benjam{\'i}n A. Carreras and Luis Garc{\'i}a and M. Angeles Pedrosa and C. Hidalgo},
  journal={Plasma Physics and Controlled Fusion},
  year={2009},
  volume={51},
  pages={065007}
}
A theoretical interpretation is given for the observed long-distance correlations in potential fluctuations in TJ-II. The value of the correlation increases above the critical point of the transition for the emergence of the plasma edge shear flow layer. Mean (i.e. surface averaged, zero-frequency) sheared flows cannot account for the experimental results. A model consisting of four envelope equations for the fluctuation level, the mean flow shear, the zonal flow amplitude shear and the… Expand

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