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The effects of vertical outflows on disk dynamos

A. Bardou·B. v. Rekowski·W. Dobler·A. Brandenburg·A. Shukurov
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Abstract

We consider the effect of vertical outflows on the mean-field dynamo in a thin disk. These outflows could be due to winds or magnetic buoyancy. We analyse both two-dimensional finite-difference numerical solutions of the axisymmetric dynamo equations and a free-decay mode expansion using the thin-disk approximation. Contrary to expectations, a vertical velocity can enhance dynamo action, provided it is not too strong. In the nonlinear regime this can lead to super-exponential growth of the magnetic field.

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A. Bardou, B. v. Rekowski, W. Dobler, A. Brandenburg, A. Shukurov. 2001-02-26. The effects of vertical outflows on disk dynamos. https://doi.org/10.1051/0004-6361%3A20010267

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