Quasi-Static 3D-Magnetic Field Evolution in Solar Active Region NOAA 11166 Associated with X1.5 Flare

Abstract

We study the quasi-static evolution of coronal magnetic fields constructed from the Non Linear Force Free Field (NLFFF) approximation aiming to understand the relation between the magnetic field topology and ribbon emission during an X1.5 flare in active region (AR) NOAA 11166. The flare with a quasi-elliptical, and two remote ribbons occurred on March 9, 2011 at 23:13UT over a positive flux region surrounded by negative flux at the center of the bipolar AR. Our analysis of the coronal magnetic structure with potential and NLFFF solutions unveiled the existence of a single magnetic null point associated with a fan-spine topology and is co-spatial with the hard X-ray source. The footpoints of the fan separatrix surface agree with the inner edge of the quasi-elliptical ribbon and the outer spine is linked to one of the remote ribbons. During the evolution, the slow footpoint motions stressed the fieldlines along the polarity inversion line and caused electric current layers in the corona around the fan separatrix surface. These current layers trigger magnetic reconnection as a consequence of dissipating currents, which are visible as cusped shape structures at lower heights. The reconnection process reorganised the magnetic field topology whose signatures are observed at the separatrices/QSL structure both in the photosphere and corona during the pre-to-post flare evolution. In agreement with previous numerical studies, our results suggest that the line-tied footpoint motions perturb the fan-spine system and cause null point reconnection, which eventually causes the flare emission at the footpoints of the fieldlines.

Accepted, 2014, The Astrophysical Journal

References in corpus (7)

• The Helioseismic and Magnetic Imager (HMI) Vector Magnetic Field Pipeline: Overview and Performance
• Non-linear force-free field modeling of a solar active region around the time of a major flare and coronal mass ejection
• Jets in coronal holes: Hinode observations and 3D computer modelling
• Generalized Squashing Factors for Covariant Description of Magnetic Connectivity in the Solar Corona
• A trilinear method for finding null points in a 3D vector space
• Current sheet formation and non-ideal behaviour at three-dimensional magnetic null points
• Magnetic Reconnection During the Two-Phase Evolution of a Solar Eruptive Flare

Cited by in corpus (17)

• Helical Kink Instability in a Confined Solar Eruption
• Sunspot Rotation as a Driver of Major Solar Eruptions in NOAA Active Region 12158
• Investigating Energetic X-Shaped Flares on the Outskirts of A Solar Active Region
• Witnessing a Large-scale Slipping Magnetic Reconnection along a Dimming Channel during a Solar Flare
• Very fast helicity injection leading to critically stable state and large eruptive activity in solar active region NOAA 12673
• Solar Flare Prediction Using Magnetic Field Diagnostics Above the Photosphere
• Onset of a Large Ejective Solar Eruption from a Typical Coronal-Jet-Base Field Configuration
• Generation mechanisms of quasi-parallel and quasi-circular flare ribbons in a confined flare
• Imaging and spectral study on the null point of a fan-spine structure during a solar flare
• Successive Injection of Opposite Magnetic Helicity in Solar Active Region NOAA 11928
• Evolutionary stages and triggering process of a complex eruptive flare with circular and parallel ribbons
• Degree of electric current neutralization and the activity in solar Active Regions
• Statistical analysis of circular-ribbon flares
• The 17 February 2013 sunquake in the context of the active region's magnetic field configuration
• Successive Injection of Opposite Magnetic Helicity: Evidence for Active Regions without Coronal Mass Ejections
• Eruption of EUV Hot-Channel near Solar Limb and Associated Moving Type-IV Radio Burst
• Formation and Eruption of a Mini-sigmoid Originating in Coronal Hole