On the cause of solar-like equatorward migration in global convective dynamo simulations
2014 (English)In: Astrophysical Journal Letters, ISSN 2041-8205, Vol. 796, no 1, L12- p.Article in journal (Refereed) Published
We present results from four convectively driven stellar dynamo simulations in spherical wedge geometry. All of these simulations produce cyclic and migrating mean magnetic fields. Through detailed comparisons, we show that the migration direction can be explained by an alpha Omega dynamo wave following the Parker-Yoshimura rule. We conclude that the equatorward migration in this and previous work is due to a positive (negative) alpha effect in the northern (southern) hemisphere and a negative radial gradient of Omega outside the inner tangent cylinder of these models. This idea is supported by a strong correlation between negative radial shear and toroidal field strength in the region of equatorward propagation.
Place, publisher, year, edition, pages
2014. Vol. 796, no 1, L12- p.
convection, dynamo, magnetohydrodynamics (MHD), Sun: activity, Sun: magnetic fields, Sun: rotation, turbulence
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:kth:diva-157595DOI: 10.1088/2041-8205/796/1/L12ISI: 000344647000012ScopusID: 2-s2.0-84909944275OAI: oai:DiVA.org:kth-157595DiVA: diva2:771069
FunderSwedish Research Council, 621-2011-5076 2012-5797
QC 201412122014-12-122014-12-112014-12-12Bibliographically approved