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This content will become publicly available on November 4, 2026

Title: Mystery behind the Peeling of a Filament and the Associated Sudden Disappearance of a Sunspot Penumbra
Abstract On 2024 July 25, while observing the solar active region NOAA 13762 with the high-resolution 1.6 m Goode Solar Telescope at the Big Bear Solar Observatory, we witnessed two mysterious phenomena: the partial detachment of filament strands from its main body in the chromosphere and the sudden disappearance of a sunspot penumbra in the photosphere, the former accompanied by small flares. Our analysis reveals a spatiotemporal correlation between the filament peeling process and the penumbral disappearance. To understand the above observations physically, we performed a magnetohydrodynamic simulation that successfully replicated the disappearance of the penumbra as a consequence of weakened horizontal magnetic field. The simulations demonstrate that both the filament peeling and the penumbral decay are driven by the same underlying process: the upward expansion of the magnetic flux rope induced by null point magnetic reconnection. These results suggest a novel mechanism by which the Sun sheds magnetic flux to interplanetary space in the form of filament peeling and penumbral disappearance.  more » « less
Award ID(s):
2114201
PAR ID:
10648204
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal Letters
Volume:
993
Issue:
2
ISSN:
2041-8205
Page Range / eLocation ID:
L47
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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