Non-linear and chaotic dynamo regimes
2012 (English)In: Proceedings of the International Astronomical Union: Vol. 8 Symposium S294, Cambridge University Press, 2012, no S294, 387-398 p.Conference paper (Refereed)
An update is given on the current status of solar and stellar dynamos. At present, it is still unclear why stellar cycle frequencies increase with rotation frequency in such a way that their ratio increases with stellar activity. The small-scale dynamo is expected to operate in spite of a small value of the magnetic Prandtl number in stars. Whether or not the global magnetic activity in stars is a shallow or deeply rooted phenomenon is another open question. Progress in demonstrating the presence and importance of magnetic helicity fluxes in dynamos is briefly reviewed, and finally the role of nonlocality is emphasized in modeling stellar dynamos using the mean-field approach. On the other hand, direct numerical simulations have now come to the point where the models show solar-like equatorward migration that can be compared with observations and that need to be understood theoretically.
Place, publisher, year, edition, pages
Cambridge University Press, 2012. no S294, 387-398 p.
, Proceedings of the International Astronomical Union, ISSN 1743-9213 ; 8
MHD, Sun: magnetic fields, turbulence
Other Physics Topics
IdentifiersURN: urn:nbn:se:kth:diva-125176DOI: 10.1017/S1743921313002822ScopusID: 2-s2.0-84880530805ISBN: 978-110703383-2OAI: oai:DiVA.org:kth-125176DiVA: diva2:639499
the International Astronomical Union 2012
QC 201308082013-08-082013-08-072013-10-01Bibliographically approved