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arXiv · 2303.05405

Eruption of a Magnetic Flux Rope in a Comprehensive Radiative Magnetohydrodynamic Simulation of flare-productive active regions

Feng Chen·Matthias Rempel·Yuhong Fan
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Abstract

Radiative magnetohydrodynamic simulation includes sufficiently realistic physics to allow for the synthesis of remote sensing observables that can be quantitatively compared with observations. We analyze the largest flare in a simulation of the emergence of large flare-productive active regions described by Chen et al. The flare releases $4.5\times10^{31}$ erg of magnetic energy and is accompanied by a spectacular coronal mass ejection. Synthetic soft X-ray flux of this flare reaches M2 class. The eruption reproduces many key features of observed solar eruptions. A pre-existing magnetic flux rope is formed along the highly sheared polarity inversion line between a sunspot pair and is covered by an overlying multi-pole magnetic field. During the eruption, the progenitor flux rope actively reconnects with the canopy field and evolves to the large-scale multi-thermal flux rope that is observed in the corona. Meanwhile, the magnetic energy released via reconnection is channeled down to the lower atmosphere and gives rise to bright soft X-ray post-flare loops and flare ribbons that reproduce the morphology and dynamic evolution of observed flares. The model helps to shed light on questions of where and when the a flux rope may form and how the magnetic structures in an eruption are related to observable emission properties.

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Feng Chen, Matthias Rempel, Yuhong Fan. 2023-03-09. Eruption of a Magnetic Flux Rope in a Comprehensive Radiative Magnetohydrodynamic Simulation of flare-productive active regions. https://doi.org/10.3847/2041-8213%2Facda2e

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