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arXiv · 0805.2138

Problems with kinematic mean field electrodynamics at high magnetic Reynolds numbers

F. Cattaneo·D. W. Hughes
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Abstract

We discuss the applicability of the kinematic $α$-effect formalism at high magnetic Reynolds numbers. In this regime the underlying flow is likely to be a small-scale dynamo, leading to the exponential growth of fluctuations. Difficulties arise with both the actual calculation of the $α$ coefficients and with its interpretation. We argue that although the former may be circumvented -- and we outline several procedures by which the the $α$ coefficients can be computed in principle -- the interpretation of these quantities in terms of the evolution of the large-scale field may be fundamentally flawed.

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F. Cattaneo, D. W. Hughes. 2008-05-14. Problems with kinematic mean field electrodynamics at high magnetic Reynolds numbers. https://doi.org/10.1111/j.1745-3933.2009.00639.x

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