Flux emergence and coronal eruption

Abstract

Our aim is to study the photospheric flux distribution of a twisted flux tube that emerges from the solar interior. We also report on the eruption of a new flux rope when the emerging tube rises into a pre-existing magnetic field in the corona. To study the evolution, we use 3D numerical simulations by solving the time-dependent and resistive MHD equations. We qualitatively compare our numerical results with MDI magnetograms of emerging flux at the solar surface. We find that the photospheric magnetic flux distribution consists of two regions of opposite polarities and elongated magnetic tails on the two sides of the polarity inversion line (PIL), depending on the azimuthal nature of the emerging field lines and the initial field strength of the rising tube. Their shape is progressively deformed due to plasma motions towards the PIL. Our results are in qualitative agreement with observational studies of magnetic flux emergence in active regions (ARs). Moreover, if the initial twist of the emerging tube is small, the photospheric magnetic field develops an undulating shape and does not possess tails. In all cases, we find that a new flux rope is formed above the original axis of the emerging tube that may erupt into the corona, depending on the strength of the ambient field.

5 pages, 3 figures, accepted for publication in A&A

References in corpus (3)

• Eruption of magnetic flux ropes during flux emergence
• The Counter-kink Rotation of a Non-Hale Active Region
• A flux emergence model for solar eruptions

Cited by in corpus (11)

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• A Cancellation Nanoflare Model for Solar Chromospheric and Coronal Heating II. 2D Theory and Simulations
• Evidence of Twisted flux-tube Emergence in Active Regions
• The emergence of magnetic flux and its role on the onset of solar dynamic events
• Evolution of microflares associated with bright points in coronal holes and in quiet regions
• High speed photospheric material flow observed at the polarity inversion line of a delta-type sunspot producing an X5.4 flare on 7 March 2012
• Active-Region Tilt Angles from White-Light Images and Magnetograms: The Role of Magnetic Tongues
• Correcting the effect of magnetic tongues on the tilt angle of bipolar active regions
• Bayesian approach for modeling solar active region global magnetic parameters
• Non-Neutralized Electric Current of Active Regions Explained as a Projection Effect