Elongation of Flare Ribbons

Abstract

We present an analysis of the apparent elongation motion of flare ribbons along the polarity inversion line (PIL) as well as the shear of flare loops in several two-ribbon flares. Flare ribbons and loops spread along the PIL at a speed ranging from a few to a hundred km/s. The shear measured from conjugate foot-points is consistent with the measurement from flare loops, and both show the decrease of shear toward a potential field as a flare evolves and ribbons and loops spread along the PIL. Flares exhibiting fast bi-directional elongation appear to have a strong shear, which may indicate a large magnetic guide field relative to the reconnection field in the coronal current sheet. We discuss how the analysis of ribbon motion could help infer properties in the corona where reconnection takes place.

References in corpus (4)

• Structures of Interplanetary Magnetic Flux Ropes and Comparison with Their Solar Sources
• The Eruption from a Sigmoidal Solar Active Region on 2005 May 13
• Partially-erupting prominences: a comparison between observations and model-predicted observables
• On the Brightening Propagation of Post-Flare Loops Observed by TRACE

Cited by in corpus (18)

• A fundamental mechanism of solar eruption initiation
• Solar Flare Arcade Modelling: Bridging the gap from 1D to 3D Simulations of Optically Thin Radiation
• External reconnection and resultant reconfiguration of overlying magnetic fields during sympathetic eruptions of two filaments
• Statistical analysis of circular-ribbon flares
• Imaging evidence for solar wind outflows originating from a CME footpoint
• Properties and Energetics of Magnetic Reconnection: I. Evolution of Flare Ribbons
• Impact of 3D Structure on Magnetic Reconnection
• A statistical Analysis of Magnetic Field Changes in the Photosphere During Solar Flares Using High-cadence Vector Magnetograms and Their Association with Flare Ribbons
• Fast degradation of the circular flare ribbon on 2014 August 24
• Flare Ribbons Approach Observed by the Interface Region Imaging Spectrograph and the Solar Dynamics Observatory
• Quantifying the Toroidal Flux of Pre-existing Flux Ropes of CMEs
• Saddle-shaped solar flare arcades
• Unveiling Spatiotemporal Properties of the Quasi-periodic Pulsations in the Balmer Continuum at 3600 Å in an X-class Solar White-light Flare
• Scaling Theory of 3D Magnetic Reconnection Spreading
• Flare Expansion to a Magnetic Rope Accompanied by Rare Radio Bursts
• Three-Dimensional Magnetic Reconnection Spreading in Current Sheets of Non-Uniform Thickness
• Global Energetics of Solar Flares: X. Petschek Reconnection Rate and Alfven Mach Number of Magnetic Reconnection Outflows
• Role of magnetic shear distribution on the formation of eruptive flux ropes