The Astrophysical Journal Letters (Jan 2024)
Comprehensive Synthesis of Magnetic Tornado: Cospatial Incidence of Chromospheric Swirls and Extreme-ultraviolet Brightening
Abstract
Magnetic tornadoes, characterized as impulsive Alfvén waves initiated by photospheric vortices in intergranular lanes, are considered efficient energy channels to the corona. Despite their acknowledged importance for solar coronal heating, their observational counterparts from the corona have not been well understood. To address this issue, we use a radiative magnetohydrodynamic simulation of a coronal loop with footpoints rooted in the upper convection zone and synthesize the chromospheric and coronal emissions corresponding to a magnetic tornado. Considering Solar Dynamics Observatory/Atmospheric Imaging Assembly 171 Å and Solar Orbiter/Extreme Ultraviolet Imager 174 Å channels, our synthesis reveals that the coronal response to magnetic tornadoes can be observed as an EUV brightening of which the width is ∼2 Mm. This brightening is located above the synthesized chromospheric swirl observed in the Ca ii 8542 Å, Ca ii K, and Mg ii k lines, which can be detected by instruments such as the Swedish 1 m Solar Telescope/CRisp Imaging SpectroPolarimeter, Goode Solar Telescope/Fast Imaging Solar Spectrograph, and Interface Region Imaging Spectrograph. Considering the height correspondence of the synthesized brightening, magnetic tornadoes can be a mechanism for the small-scale EUV brightenings such as the solar “campfires.” Our findings indicate that coordinated observations encompassing the chromosphere to the corona are indispensable for comprehending the origin of coronal EUV brightenings.
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