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arXiv · 1712.07377

Thermal responses in a coronal loop maintained by wave heating mechanisms

Takuma Matsumoto
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Abstract

A full 3-dimensional compressible magnetohydrodynamic (MHD) simulation is conducted to investigate the thermal responses of a coronal loop to the dynamic dissipation processes of MHD waves. When the foot points of the loop are randomly and continuously forced, the MHD waves become excited and propagate upward. Then, a 1-MK temperature corona is produced naturally as the wave energy dissipates. The excited wave packets become non-linear just above the magnetic canopy, and the wave energy cascades into smaller spatial scales. Moreover, collisions between counter-propagating Alfvén wave packets increase the heating rate, resulting in impulsive temperature increases. Our model demonstrates that the heating events in the wave-heated loops can be nanoflare-like in the sense that they are spatially localized and temporally intermittent.

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Takuma Matsumoto. 2018-02-27. Thermal responses in a coronal loop maintained by wave heating mechanisms. https://doi.org/10.1093/mnras%2Fsty490

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