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Title: Vortex and Sink Flows in Eruptive Flares as a Model for Coronal Implosions

Abstract

Eruptive flares are sudden releases of magnetic energy that involve many phenomena, several of which can be explained by the standard 2D flare model and its realizations in 3D. We analyze a 3D magnetohydrodynamics simulation, in the framework of this model, that naturally explains the contraction of coronal loops in the proximity of the flare sites, as well as the inflow toward the region above the cusp-shaped loops. We find that two vorticity arcs located along the flanks of the erupting magnetic flux rope are generated as soon as the eruption begins. The magnetic arcades above the flux rope legs are then subjected to expansion, rotation, or contraction depending on which part of the vortex flow advects them. In addition to the vortices, an inward-directed magnetic pressure gradient exists in the current sheet below the magnetic flux rope. It results in the formation of a sink that is maintained by reconnection. We conclude that coronal loop apparent implosions observed during eruptive flares are the result of hydromagnetic effects related to the generation of vortex and sink flows when a flux rope moves in a magnetized environment.

Authors:
 [1]; ; ;  [2];  [3];  [4]
  1. Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, B-3001 Leuven (Belgium)
  2. LESIA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris-Diderot, Sorbonne Paris Cit’e, 5 place Jules Janssen, F-92195 Meudon (France)
  3. Astronomical Institute of the Academy of Sciences of the Czech Republic, Fričova 298, 251 65 Ondřejov (Czech Republic)
  4. NorthWest Research Associates, 3380 Mitchell Lane, Boulder, CO 80301 (United States)
Publication Date:
OSTI Identifier:
22661293
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 837; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; EXPANSION; IMPLOSIONS; MAGNETIC FLUX; MAGNETOHYDRODYNAMICS; PRESSURE GRADIENTS; ROTATION; SIMULATION; SINKS; SUN; VORTEX FLOW

Citation Formats

Zuccarello, F. P., Aulanier, G., Démoulin, P., Schmieder, B., Dudík, J., and Gilchrist, S. A., E-mail: francesco.zuccarello@wis.kuleuven.be, E-mail: dudik@asu.cas.cz. Vortex and Sink Flows in Eruptive Flares as a Model for Coronal Implosions. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6110.
Zuccarello, F. P., Aulanier, G., Démoulin, P., Schmieder, B., Dudík, J., & Gilchrist, S. A., E-mail: francesco.zuccarello@wis.kuleuven.be, E-mail: dudik@asu.cas.cz. Vortex and Sink Flows in Eruptive Flares as a Model for Coronal Implosions. United States. doi:10.3847/1538-4357/AA6110.
Zuccarello, F. P., Aulanier, G., Démoulin, P., Schmieder, B., Dudík, J., and Gilchrist, S. A., E-mail: francesco.zuccarello@wis.kuleuven.be, E-mail: dudik@asu.cas.cz. Fri . "Vortex and Sink Flows in Eruptive Flares as a Model for Coronal Implosions". United States. doi:10.3847/1538-4357/AA6110.
@article{osti_22661293,
title = {Vortex and Sink Flows in Eruptive Flares as a Model for Coronal Implosions},
author = {Zuccarello, F. P. and Aulanier, G. and Démoulin, P. and Schmieder, B. and Dudík, J. and Gilchrist, S. A., E-mail: francesco.zuccarello@wis.kuleuven.be, E-mail: dudik@asu.cas.cz},
abstractNote = {Eruptive flares are sudden releases of magnetic energy that involve many phenomena, several of which can be explained by the standard 2D flare model and its realizations in 3D. We analyze a 3D magnetohydrodynamics simulation, in the framework of this model, that naturally explains the contraction of coronal loops in the proximity of the flare sites, as well as the inflow toward the region above the cusp-shaped loops. We find that two vorticity arcs located along the flanks of the erupting magnetic flux rope are generated as soon as the eruption begins. The magnetic arcades above the flux rope legs are then subjected to expansion, rotation, or contraction depending on which part of the vortex flow advects them. In addition to the vortices, an inward-directed magnetic pressure gradient exists in the current sheet below the magnetic flux rope. It results in the formation of a sink that is maintained by reconnection. We conclude that coronal loop apparent implosions observed during eruptive flares are the result of hydromagnetic effects related to the generation of vortex and sink flows when a flux rope moves in a magnetized environment.},
doi = {10.3847/1538-4357/AA6110},
journal = {Astrophysical Journal},
number = 2,
volume = 837,
place = {United States},
year = {Fri Mar 10 00:00:00 EST 2017},
month = {Fri Mar 10 00:00:00 EST 2017}
}
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