Ejections of Magnetic Structures Above a Spherical Wedge Driven by a Convective Dynamo with Differential Rotation
2012 (English)In: Solar Physics, ISSN 0038-0938, E-ISSN 1573-093X, Vol. 280, no 2, 299-319 p.Article in journal (Refereed) Published
We combine a convectively driven dynamo in a spherical shell with a nearly isothermal density-stratified cooling layer that mimics some aspects of a stellar corona to study the emergence and ejections of magnetic field structures. This approach is an extension of earlier models, where forced turbulence simulations were employed to generate magnetic fields. A spherical wedge is used which consists of a convection zone and an extended coronal region to a parts per thousand aEuro parts per thousand 1.5 times the radius of the sphere. The wedge contains a quarter of the azimuthal extent of the sphere and 150(a similar to) in latitude. The magnetic field is self-consistently generated by the turbulent motions due to convection beneath the surface. Magnetic fields are found to emerge at the surface and are ejected to the coronal part of the domain. These ejections occur at irregular intervals and are weaker than in earlier work. We tentatively associate these events with coronal mass ejections on the Sun, even though our model of the solar atmosphere is rather simplistic.
Place, publisher, year, edition, pages
2012. Vol. 280, no 2, 299-319 p.
Magnetic fields, corona, Coronal mass ejections, theory, Interior, convective zone, Turbulence, Helicity current
IdentifiersURN: urn:nbn:se:kth:diva-105015DOI: 10.1007/s11207-012-0108-4ISI: 000309865800002ScopusID: 2-s2.0-84867507839OAI: oai:DiVA.org:kth-105015DiVA: diva2:570314
FunderEU, FP7, Seventh Framework Programme, 228398EU, European Research Council, 227952Swedish Research Council, 621-2007-4064
QC 201211192012-11-192012-11-152013-08-28Bibliographically approved