Skip to Main content Skip to Navigation
Journal articles

Global Dynamics of Subsurface Solar Active Regions

Abstract : 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 by the convective motions and the presence of a differential rotation in the convective cases.
Complete list of metadatas

Cited literature [76 references]  Display  Hide  Download

https://hal-cea.archives-ouvertes.fr/cea-00827728
Contributor : Bruno Savelli <>
Submitted on : Thursday, October 17, 2019 - 3:28:04 PM
Last modification on : Thursday, October 15, 2020 - 4:07:16 AM
Long-term archiving on: : Saturday, January 18, 2020 - 2:26:52 PM

File

jou.pdf
Publisher files allowed on an open archive

Identifiers

Citation

L. Jouve, A.S. Brun, G. Aulanier. Global Dynamics of Subsurface Solar Active Regions. The Astrophysical Journal, American Astronomical Society, 2013, 762 (4), ⟨10.1088/0004-637X/762/1/4⟩. ⟨cea-00827728⟩

Share

Metrics

Record views

475

Files downloads

836