Horizontal photospheric flows trigger a filament eruption

Abstract

A large filament composed principally of two sections erupted sequentially in the southern hemisphere on January 26 2016. The central, thick part of the northern section was first lifted up and lead to the eruption of the full filament. This event was observed in H-alpha with GONG and CLIMSO, and in ultraviolet (UV) with the AIA/SDO imager. The aim of the paper is to relate the photospheric motions below the filament and its environment to the eruption of the filament. An analysis of the photospheric motions using SDO/HMI continuum images with the coherent structure tracking (CST) algorithm developed to track granules, as well as large-scale photospheric flows, has been performed. The supergranule pattern is clearly visible outside the filament channel but difficult to detect inside because the modulus of the vector velocity is reduced in the filament channel, mainly in the magnetized areas. The horizontal photospheric flows are strong on the west side of the filament channel and oriented towards the filament. The ends of the filament sections are found in areas of concentration of corks. Whirled flows are found locally around the feet. The strong horizontal flows with an opposite direction to the differential rotation create strong shear and convergence along the magnetic polarity inversion line (PIL) in the filament channel. The filament has been destabilized by the converging flows, which initiate an ascent of the middle section of the filament until the filament reaches the critical height of the torus instability inducing, consequently, the eruption. The "n" decay index indicated an altitude of 60 Mm for the critical height. It is conjectured that the convergence along the PIL is due to the large-scale size cells of convection that transport the magnetic field to their borders.

10 pages, 9 figures

References in corpus (13)

• Torus instability
• Tracking Vector Magnetograms with the Magnetic Induction Equation
• Photospheric flux cancellation and associated flux rope formation and eruption
• Numerical simulations of fast and slow coronal mass ejections
• Catastrophe versus instability for the eruption of a toroidal solar magnetic flux rope
• Flux cancellation and the evolution of the eruptive filament of 2011 June 7
• Large-Amplitude Longitudinal Oscillations Triggered by the Merging of Two Solar Filaments: Observations and Magnetic Field Analysis
• Tracking granules on the Sun's surface and reconstructing horizontal velocity fields: I. the CST algorithm
• Supergranulation and multiscale flows in the solar photosphere: Global observations vs. a theory of anisotropic turbulent convection
• Large-scale horizontal flows in the solar photosphere III: Effects on filament destabilization
• Interaction of two filaments in a long filament channel associated with twin coronal mass ejections
• Large-scale photospheric motions determined from granule tracking and helioseismology from SDO/HMI data
• Interaction of Two Filament Channels of Different Chiralities

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