Saddle-shaped Solar Flare Arcades

Abstract Arcades of flare loops form as a consequence magnetic reconnection powering solar flares and eruptions. We analyze the morphology evolution arcades that formed during five well-known eruptive flares. show have common saddle-like shape. The saddles occur despite fact were different classes (C to X), occurred in environments, observed various projections. are related presence longer, relatively higher, inclined loops, consistently at ends arcades, which we term “cantles.” Our observations indicate cantles typically join straight portions ribbons with hooked extensions conjugate ribbons. origin is investigated stereoscopic 2011 May 9 carried out by Atmospheric Imaging Assembly Extreme Ultraviolet Imager. mutual separation instruments led ideal observational conditions allowing for simultaneous analysis evolving cantle underlying ribbon hook. Based on our suggest formation one can be explained between erupting structure its overlying arcades. propose provide information about geometries individual originate.