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arXiv · 2003.08131

Various scenarios for the equatorward migration of sunspots

Detlef Elstner·Yori Fournier·Rainer Arlt
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Abstract

The profile of the differential rotation together with the sign of the alpha-effect determine the dynamo wave direction. In early models of the solar dynamo the dynamo wave often leads to a poleward migration of the activity belts. Flux transport by the meridional flow or the effect of the surface shear layer are possible solutions. In a model including the corona, we show that various migrations can be obtained by varying the properties of the corona. A new dynamo of Babcock-Leighton type also leads to the correct equatorward migration by the non-linear relation between flux density and rise time of the flux.

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Detlef Elstner, Yori Fournier, Rainer Arlt. 2020-03-18. Various scenarios for the equatorward migration of sunspots. https://doi.org/10.1017/s1743921319009888

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