Relation between Flare Ribbon and 3D Magnetic Field Topology and Flare Eruptivity

Authors: Tamima Saba (Georgia State University), Viacheslav Sadykov (Georgia State University), Griffin Goodwin (Georgia State University), Petrus Martens (Georgia State University)

Flares can be eruptive or confined depending on whether they are accompanied by a Coronal Mass Ejection (CME). The shape of flare ribbons, a phenomenon occurring at the footpoints of magnetic field loops in the chromosphere, imprints the topology of the 3D magnetic fields and can be connected to event eruptivity. Based on the Standard Flare Model, it has long been argued that a two-ribbon flare is likely to result in an eruption. In this work, we study the relation between the eruptivity and two-ribbon topology in the flares of different soft X-ray (SXR) classes using a catalog of 722 solar flares from Solar Cycle 24 from Kazachenko et al. (2023).  Using observations in 1600 Å channel from the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO), we generate the desaturated GIF movies of flare ribbon dynamics for all events and quantify their two-ribbon nature based on the experts’ input. For C and M-class flares, it has been observed that the more likely the flare demonstrates the two-ribbon topology, the more likely it is to be eruptive. The eruptivity probability does not seem to depend on the ribbon topology for the X-class flares. For the flare of the particular class very confidently identified as two-ribbon, the eruptivity chances are ~45% (C-class) and ~70% (M-class and X-class). We also find that if the eruptive C-class and M-class flares do not show the two-ribbon topology signatures, these are likely circular ribbon flares. Given that flare ribbons imprint the magnetic field topology in the chromosphere, we currently investigate the properties of the 3D reconstructed Non-Linear Force-Free Fields (NLFFFs) in the active regions of interest and their relation to both flare ribbons and the eruptivity process.