Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-19T12:46:12.470Z Has data issue: false hasContentIssue false

Dynamo generated field emergence through recurrent plasmoid ejections

Published online by Cambridge University Press:  26 August 2011

Jörn Warnecke
Affiliation:
Nordita, AlbaNova University Center, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden email: [email protected] Department of Astronomy, AlbaNova University Center, Stockholm University, SE 10691 Stockholm, Sweden
Axel Brandenburg
Affiliation:
Nordita, AlbaNova University Center, Roslagstullsbacken 23, SE-10691 Stockholm, Sweden email: [email protected] Department of Astronomy, AlbaNova University Center, Stockholm University, SE 10691 Stockholm, Sweden
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Magnetic buoyancy is believed to drive the transport of magnetic flux tubes from the convection zone to the surface of the Sun. The magnetic fields form twisted loop-like structures in the solar atmosphere. In this paper we use helical forcing to produce a large-scale dynamo-generated magnetic field, which rises even without magnetic buoyancy. A two layer system is used as computational domain where the upper part represents the solar atmosphere. Here, the evolution of the magnetic field is solved with the stress–and–relax method. Below this region a magnetic field is produced by a helical forcing function in the momentum equation, which leads to dynamo action. We find twisted magnetic fields emerging frequently to the outer layer, forming arch-like structures. In addition, recurrent plasmoid ejections can be found by looking at space–time diagrams of the magnetic field. Recent simulations in spherical coordinates show similar results.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2011

References

Gudiksen, B. V. & Nordlund, . 2005, Astrophys. J., 618, 1031CrossRefGoogle Scholar
Käpylä, P. J., Korpi, M. J., & Brandenburg, A. 2008, Astron. Astrophys, 491, 353CrossRefGoogle Scholar
Nordlund, Å., Brandenburg, A., Jennings, R. L., Rieutord, M., Ruokolainen, J., Stein, R. F., & Tuominen, I. 1992, Astrophys. J., 392, 647CrossRefGoogle Scholar
Parker, E. N. 1979 Cosmical magnetic fields Clarendon Press, OxfordGoogle Scholar
Tobias, S. M., Brummell, N. H., Clune, T. L., & Toomre, J. 1998, Astrophys. J. Lett., 502, L177CrossRefGoogle Scholar
Valori, G., Kliem, B., & Keppens, R. 2005, Astron. Astrophys, 433, 335CrossRefGoogle Scholar
Warnecke, J. & Brandenburg, A.Astron. Astrophys, 2010, 523, A19CrossRefGoogle Scholar
Warnecke, J., Brandenburg, A., & Mitra, D., 2011, A&A (submitted), arXiv:1104.0664Google Scholar