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  • High-resolution Observation and Magnetic Modeling of a Solar Minifilament: The Formation, Eruption, and Failing Mechanisms
Title: High-resolution Observation and Magnetic Modeling of a Solar Minifilament: The Formation, Eruption, and Failing Mechanisms
Abstract Minifilaments are widespread small-scale structures in the solar atmosphere. To better understand their formation and eruption mechanisms, we investigate the entire life of a sigmoidal minifilament located below a large quiescent filament observed by Big Bear Solar Observatory/Goode Solar Telescope on 2015 August 3. The Hαstructure initially appears as a group of arched threads, then transforms into two J-shaped arcades, and finally forms a sigmoidal shape. Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly observations in 171 Å show that two coronal jets occur around the southern footpoint of the minifilament before the minifilament eruption. The minifilament eruption starts from the southern footpoint, then interacts with the overlying filament and fails. The aforementioned observational changes correspond to three episodes of flux cancellations observed by SDO/Helioseismic and Magnetic Imager. Unlike previous studies, the flux cancellation occurs between the polarity where the southern footpoint of the minifilament is rooted and an external polarity. We construct two magnetic field models before the eruption using the flux rope insertion method and find a hyperbolic flux tube above the flux cancellation site. The observation and modeling results suggest that the eruption is triggered by the external magnetic reconnection between the core field of the minifilament and the external fields due to flux cancellations. This study reveals a new triggering mechanism for minifilament eruptions and a new relationship between minifilament eruptions and coronal jets.  more » « less
Award ID(s):
2309939 1821294 2108235
PAR ID:
10535785
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
American Astronomical Society
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
970
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
100
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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