Intermittent structures and magnetic discontinuities on small scales in MHD simulations and solar wind

Abstract

In this work we review some recent studies, in which properties of the magnetic field in high resolution simulations of MHD turbulence with spacecraft data are compared, focusing on methods used to identify classical discontinuities and intermittency statistics. Comparison of ACE solar wind data and simulations of MHD turbulence showed good agreement in waiting-time analysis of magnetic discontinuities, and in the related distribution of magnetic field increments. Further analyses showed that the magnetic discontinuities are not distributed without correlations, but rather that non-Poisson correlations, possibly in the form of burstiness or voids, are present in the data at least up to the typical correlation scale. The discontinuities or bursty coherent structures represent in this view the current sheets that form between magnetic flux tubes which may be a signature of intermittent, anisotropic, fully developed MHD turbulence. © 2010 Elsevier Ltd. All rights reserved. All rights reserved.