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arXiv · 1005.1640

Magnetohydrodynamic Turbulent Cascade of Coronal Loop Magnetic Fields

A. F. Rappazzo·M. Velli
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Abstract

The Parker model for coronal heating is investigated through a high resolution simulation. An inertial range is resolved where fluctuating magnetic energy E_M (k_perp) \propto k_\perp^{-2.7} exceeds kinetic energy E_K (k_\perp) \propto k_\perp^{-0.6}. Increments scale as δb_\ell \simeq \ell^{-0.85} and δu_\ell \simeq \ell^{+0.2} with velocity increasing at small scales, indicating that magnetic reconnection plays a prime role in this turbulent system. We show that spectral energy transport is akin to standard magnetohydrodynamic (MHD) turbulence even for a system of reconnecting current sheets sustained by the boundary. In this new MHD turbulent cascade, kinetic energy flows are negligible while cross-field flows are enhanced, and through a series of "reflections" between the two fields, cascade more than half of the total spectral energy flow.

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A. F. Rappazzo, M. Velli. 2011-06-09. Magnetohydrodynamic Turbulent Cascade of Coronal Loop Magnetic Fields. https://doi.org/10.1103/physreve.83.065401

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