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Title: GLOBAL DYNAMICS OF SUBSURFACE SOLAR ACTIVE REGIONS

We present three-dimensional numerical simulations of a magnetic loop evolving in either a convectively stable or unstable rotating shell. The magnetic loop is introduced into the shell in such a way that it is buoyant only in a certain portion in longitude, thus creating an {Omega}-loop. Due to the action of magnetic buoyancy, the loop rises and develops asymmetries between its leading and following legs, creating emerging bipolar regions whose characteristics are similar to those of observed spots at the solar surface. In particular, we self-consistently reproduce the creation of tongues around the spot polarities, which can be strongly affected by convection. We further emphasize the presence of ring-shaped magnetic structures around our simulated emerging regions, which we call 'magnetic necklace' and which were seen in a number of observations without being reported as of today. We show that those necklaces are markers of vorticity generation at the periphery and below the rising magnetic loop. We also find that the asymmetry between the two legs of the loop is crucially dependent on the initial magnetic field strength. The tilt angle of the emerging regions is also studied in the stable and unstable cases and seems to be affected both bymore » the convective motions and the presence of a differential rotation in the convective cases.« less
Authors:
 [1] ;  [2] ;  [3]
  1. UPS-OMP, Institut de Recherche en Astrophysique et Planetologie, Universite de Toulouse CNRS, 14 Avenue Edouard Belin, F-31400 Toulouse (France)
  2. Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot, IRFU/SAp, F-91191 Gif sur Yvette (France)
  3. LESIA, Observatoire de Paris, CNRS, UPMC, Universite Paris-Diderot, 5 Place Jules Janssen, F-92190 Meudon Cedex (France)
Publication Date:
OSTI Identifier:
22167365
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 762; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; ASYMMETRY; COMPUTERIZED SIMULATION; CONVECTION; INTERPLANETARY MAGNETIC FIELDS; MAGNETIC FLUX; MAGNETOHYDRODYNAMICS; ROTATION; SUN; THREE-DIMENSIONAL CALCULATIONS