A solar flare disturbing a light wall above a sunspot light bridge

Abstract

With the high-resolution data from the Interface Region Imaging Spectrograph, we detect a light wall above a sunspot light bridge in the NOAA active region (AR) 12403. In the 1330 A slit-jaw images, the light wall is brighter than the ambient areas while the wall top and base are much brighter than the wall body, and it keeps oscillating above the light bridge. A C8.0 flare caused by a filament activation occurred in this AR with the peak at 02:52 UT on 2015 August 28, and the flare's one ribbon overlapped the light bridge which was the observational base of the light wall. Consequently, the oscillation of the light wall was evidently disturbed. The mean projective oscillation amplitude of the light wall increased from 0.5 Mm to 1.6 Mm before the flare, and decreased to 0.6 Mm after the flare. We suggest that the light wall shares a group of magnetic field lines with the flare loops, which undergo a magnetic reconnection process, and they constitute a coupled system. When the magnetic field lines are pushed upwards at the pre-flare stage, the light wall turns to the vertical direction, resulting in the increase of the light wall's projective oscillation amplitude. After the magnetic reconnection takes place, a group of new field lines with smaller scales are formed underneath the reconnection site and the light wall inclines. Thus, the projective amplitude decreases remarkably at the post-flare stage.

6 pages, 4 figures, Accepted for publication in ApJL

References in corpus (4)

• Quasi-periodic Slipping Magnetic Reconnection During an X-class Solar Flare Observed by the Solar Dynamics Observatory and Interface Region Imaging Spectrograph
• Observations of Subarcsecond Bright Dots in the Transition Region above Sunspots with the Interface Region Imaging Spectrograph
• Small-scale chromospheric jets above a sunspot light bridge
• Oscillating light wall above a sunspot light bridge

Cited by in corpus (9)

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• External reconnection and resultant reconfiguration of overlying magnetic fields during sympathetic eruptions of two filaments
• Enhancement of a sunspot light wall with external disturbances
• Sunspot Light Walls Suppressed by Nearby Brightenings
• Sunspot penumbral filaments intruding into a light bridge and the resultant reconnection jets
• Signatures of the impact of flare ejected plasma on the photosphere of a sunspot light-bridge
• Small-scale Bright Blobs Ejected from a Sunspot Light Bridge
• Light Bridges Can Suppress the Formation of Coronal Loops
• Various Activities above Sunspot Light Bridges in IRIS Observations: Classification and Comparison