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arXiv · 1110.2932

Nonaxisymmetric Anisotropy of Solar Wind Turbulence as a Direct Test for the Models of Magnetohydrodynamic Tubulence

A. J. Turner·G. Gogoberidze·S. C. Chapman
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Abstract

Single point spacecraft observations of the turbulent solar wind flow exhibit a characteristic nonaxisymmetric anisotropy that depends sensitively on the perpendicular power spectral exponent. For the first time we use this nonaxisymmetric anisotropy as a function of wave vector direction to test models of magnetohydrodynamic (MHD) turbulence. Using Ulysses magnetic field observations in the fast, quiet polar solar wind we find that the Goldreich-Sridhar model of MHD turbulence is not consistent with the observed anisotropy, whereas the observations are well reproduced by the "Slab + 2D" model. The Golderich-Sridhar model alone can not account for the observations unless an additional component is also present.

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A. J. Turner, G. Gogoberidze, S. C. Chapman. 2011-10-13. Nonaxisymmetric Anisotropy of Solar Wind Turbulence as a Direct Test for the Models of Magnetohydrodynamic Tubulence. https://doi.org/10.1103/physrevlett.108.085001

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