K. T. Osman, W. H. Matthaeus, M. Wan, A. F. Rappazzo
Evidence for inhomogeneous heating in the interplanetary plasma near current
sheets dynamically generated by magnetohydrodynamic (MHD) turbulence is
obtained using measurements from the ACE spacecraft. These coherent structures
only constitute 19% of the data, but contribute 50% of the total plasma
internal energy. Intermittent heating manifests as elevations in proton
temperature near current sheets, resulting in regional heating and temperature
enhancements extending over several hours. The number density of non-Gaussian
structures is found to be proportional to the mean proton temperature and solar
wind speed. These results suggest magnetofluid turbulence drives intermittent
dissipation through a hierarchy of coherent structures, which collectively
could be a significant source of coronal and solar wind heating.
View original:
http://arxiv.org/abs/1111.6921
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