Small Scale Kinematic Dynamos: Beyond the α-Effect |
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| Authors: | A Tilgner |
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| Institution: | Institute of Geophysics , University of G?ttingen , Herzberger Landster. 180, D-37075 G?ttingen , Germany |
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| Abstract: | In geodynamo simulations which simulate the generation of an axial dipolar magnetic field, the generation mechanism appears to be adequately described as an α2-dynamo with an anisotropic α-effect. The anisotropy in the α-effect favors an equatorial dipole field, however, which calls into question the interpretation in terms of an α2-dynamo. It is shown in this article with kinematic dynamo calculations and exemplary velocity fields with an anisotropic α-effect that both types of dipolar magnetic field can be generated. Two examples of working dynamos in a sphere with flows with zero α-effect are also provided. |
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| Keywords: | Dynamo effect Mean-field theory |
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