Turbulence in the Solar Wind

The solar wind is, apparently, a turbulent medium permeated by fluctuations on a broad range of scales characterizing the plasma as a fluid and kinetic entity. Here we briefly review some recent developments and observations on MHD fluctuations in the frequency range between some 10−6 and 10−2 Hz. Spectral analysis reveals that solar wind fluctuations represent ongoing turbulence, often with high Alfvenic correlations of coronal origin, which undergoes considerable spatial and spectral evolution in the radially expanding wind and is coupled to large-scale plasma structures and magnetic field inhomogeneities. Theoretical attempts to model the transport of magnetohydrodynamic fluctuations are discussed. Finally, the dissipation of turbulence and concurrent heating of the wind are addressed.

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