DYNAMIC COUPLING OF CONVECTIVE FLOWS AND MAGNETIC FIELD DURING FLUX EMERGENCE

Journal Article · Fri Jan 20 04:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/745/1/37· OSTI ID:22012000

Fang, Fang; Manchester, IV, Ward; Van der Holst, Bart ^[1]; Abbett, William P ^[2]

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1. Department of Atmospheric, Oceanic and Space Sciences, University of Michigan, Ann Arbor, MI 48109 (United States)
2. Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States)

We simulate the buoyant rise of a magnetic flux rope from the solar convection zone into the corona to better understand the energetic coupling of the solar interior to the corona. The magnetohydrodynamic model addresses the physics of radiative cooling, coronal heating, and ionization, which allow us to produce a more realistic model of the solar atmosphere. The simulation illustrates the process by which magnetic flux emerges at the photosphere and coalesces to form two large concentrations of opposite polarities. We find that the large-scale convective motion in the convection zone is critical to form and maintain sunspots, while the horizontal converging flows in the near-surface layer prevent the concentrated polarities from separating. The footpoints of the sunspots in the convection zone exhibit a coherent rotation motion, resulting in the increasing helicity of the coronal field. Here, the local configuration of the convection causes the convergence of opposite polarities of magnetic flux with a shearing flow along the polarity inversion line. During the rising of the flux rope, the magnetic energy is first injected through the photosphere by the emergence, followed by energy transport by horizontal flows, after which the energy is subducted back to the convection zone by the submerging flows.

• OSTI ID: 22012000
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 745; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CONVECTION
IONIZATION
MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETOHYDRODYNAMICS
PHOTOSPHERE
RADIATIVE COOLING
ROTATION
SUN
SUNSPOTS