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arXiv · 2509.04329

Characterizing Vortex-Driven Dynamics in the Solar Atmosphere Using Information Theory

Suzana S. A. Silva·Erico Rempel·Gary Verth·Istvan Ballai·Viktor Fedun
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Abstract

Solar vortex regions show enhanced Poynting flux and favourable heating conditions, but how the vortices reorganize and influence their surroundings remains unclear. Here we apply information-theoretic diagnostics to a Bifrost simulation to quantify the dynamics of a long-lived vortex. By combining Shannon Entropy and Normalized Mutual Information, we track how the vortex reshapes plasma-magnetic couplings and modifies local thermodynamics. The vortex originates in the upper photosphere and extends into the chromosphere, where it suppresses the background p-mode-like organisation seen in the neighbouring magnetic flux tube. Shannon Entropy analysis shows that magnetic complexity rises sharply as the vortex develops, which is consistent with the build-up of currents and stored energy. At the same time, temperature becomes more strongly linked to magnetic shear, pointing to heating associated with current dissipation. The way temperature responds to different heating processes also changes with height: in the photosphere and lower chromosphere, it follows local compressional and expansion motions, while in the upper atmosphere, it is influenced mainly by viscous and current-driven effects. During this phase, the usual temperature-density relationship weakens, indicating that the plasma departs from purely adiabatic behaviour. Applying the same diagnostics to a nearby non-vortical flux tube yields only weak, uniform couplings, which confirms that the enhanced links are vortex-driven. Together, these results demonstrate that a coherent solar vortex not only drives heating but also reconfigures the local atmosphere, replacing periodic pressure-driven behaviour with magnetically dominated dynamics.

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Suzana S. A. Silva, Erico Rempel, Gary Verth, Istvan Ballai, Viktor Fedun. 2025-09-04. Characterizing Vortex-Driven Dynamics in the Solar Atmosphere Using Information Theory. https://arxiv.org/abs/2509.04329

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