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arXiv · 2306.05388

Hybrid data-driven magnetofrictional and magnetohydrodynamic simulations of an eruptive solar active region

A. Afanasyev·Y. Fan·M. Kazachenko·M. Cheung
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Abstract

We present first results of the hybrid data-driven magnetofrictional (MF) and data-constrained magnetohydrodynamic (MHD) simulations of solar active region NOAA 11158, which produced an X-class flare and coronal mass ejection on 2011 February 15. First, we apply the MF approach to build the coronal magnetic configuration corresponding to the SDO/HMI photospheric magnetograms by using the JSOC PDFI SS electric field inversions at the bottom boundary of the simulation domain. We then use the pre-eruptive MF state at about 1.5 hour before the observed X-class flare as the initial state for the MHD simulation, assuming a stratified polytropic solar corona. The MHD run shows that the initial magnetic configuration containing twisted magnetic fluxes and a 3D magnetic null point is out of equilibrium. We find the eruption of a complex magnetic structure consisting of two magnetic flux ropes, as well as the development of flare ribbons, with their morphology being in good agreement with observations. We conclude that the combination of the data-driven MF and data-constrained MHD simulations is a useful practical tool for understanding the 3D magnetic structures of real solar ARs that are unobservable otherwise.

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A. Afanasyev, Y. Fan, M. Kazachenko, M. Cheung. 2023-06-08. Hybrid data-driven magnetofrictional and magnetohydrodynamic simulations of an eruptive solar active region. https://doi.org/10.3847/1538-4357%2Facd7e9

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