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arXiv · 1208.3141

MHD Waves and Coronal Heating: Unifying Empirical and MHD Turbulence Models

Igor V. Sokolov·Bart van der Holst·Rona Oran·Cooper Downs·Ilia I. Roussev·Meng Jin·Ward B. Manchester IV·Rebekah M. Evans·Tamas I. Gombosi
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Abstract

We present a new global model of the solar corona, including the low corona, the transition region and the top of chromosphere. The realistic 3D magnetic field is simulated using the data from the photospheric magnetic field measurements. The distinctive feature of the new model is incorporating the MHD Alfven wave turbulence. We assume this turbulence and its non-linear dissipation to be the only momentum and energy source for heating the coronal plasma and driving the solar wind. The difference between the turbulence dissipation efficiency in coronal holes and that in closed field regions is because the non-linear cascade rate degrades in strongly anisotropic turbulence in coronal holes (no inward propagating wave), thus resulting in colder coronal holes with the bi-modal solar wind originating from them. The detailed presentation of the theoretical model is illustrated with the synthetic images for multi-wavelength EUV emission compared with the observations from SDO AIA and Stereo EUVI instruments for the Carrington rotation 2107.

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Igor V. Sokolov, Bart van der Holst, Rona Oran, Cooper Downs, Ilia I. Roussev, Meng Jin, Ward B. Manchester IV, Rebekah M. Evans, Tamas I. Gombosi. 2012-12-05. MHD Waves and Coronal Heating: Unifying Empirical and MHD Turbulence Models. https://doi.org/10.1088/0004-637x%2F764%2F1%2F23

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