A dynamo model for axisymmetric and non-axisymmetric solar magnetic fields

Abstract

Increasing observations are becoming available about a relatively weak, but persistent, non-axisymmetric magnetic field co-existing with the dominant axisymmetric field on the Sun. It indicates that the non-axisymmetric magnetic field plays an important role in the origin of solar activity. A linear non-axisymmetric alpha2-Omega dynamo model is set up to discuss the characteristics of the axisymmetric m=0 and the first non-axisymmetric m=1 modes and to provide further the theoretical bases to explain the active longitude, flip-flop and other non-axisymmetric phenomena. The model consists of a updated solar internal differential rotation, a turbulent diffusivity varied with depth and an alpha-effect working at the tachocline in rotating spherical systems. The difference between the alpha2-Omega and the alpha-Omega models and the conditions to favor the non-axisymmetric modes with the solar-like parameters are also presented.

9 pages, 9 figures, and 2 tabels; MNRAS accepted

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Cited by in corpus (4)

• A Double-Ring Algorithm for Modeling Solar Active Regions: Unifying Kinematic Dynamo Models and Surface Flux-Transport Simulations
• a dynamo-based prediction of solar cycle 25
• Modeling effects of starspots on stellar magnetic cycles
• An efficient method for computing the eigenfunctions of the dynamo equation