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arXiv · 1412.0997

Dynamical quenching with non-local alpha and downward pumping

A. Brandenburg·A. Hubbard·P. J. Käpylä
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Abstract

In light of new results, the one-dimensional mean-field dynamo model of Brandenburg & Kapyla (2007) with dynamical quenching and a nonlocal Babcock-Leighton alpha effect is re-examined for the solar dynamo. We extend the one-dimensional model to include the effects of turbulent downward pumping (Kitchatinov & Olemskoy 2011), and to combine dynamical quenching with shear. We use both the conventional dynamical quenching model of Kleeorin & Ruzmaikin (1982) and the alternate one of Hubbard & Brandenburg (2011), and confirm that with varying levels of non-locality in the alpha effect, and possibly shear as well, the saturation field strength can be independent of the magnetic Reynolds number.

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A. Brandenburg, A. Hubbard, P. J. Käpylä. 2014-12-02. Dynamical quenching with non-local alpha and downward pumping. https://doi.org/10.1002/asna.201412141

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