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Dynamo mechanism: Effects of correlations and viscosities

Abhik Basu
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Abstract

We analyze the effects of the background velocity and the initial magnetic field correlations, and viscosities on the turbulent dynamo and the α-effect. We calculate the α-coefficients for arbitrary magnetic and fluid viscosities, background velocity and the initial magnetic field correlations. We explicitly demonstrate that the general features of the initial growth and late-time saturation of the magnetic fields due to the non-linear feedback are qualitatively independent of these correlations. We also examine the hydrodynamic limit of the magnetic field growth in a renormalization group framework and discuss the possibilities of suppression of the dynamo growth below a critical rotation. We demonstrate that for Kolmogorov- (K41) type of spectra the Ekman number M >1/2 for dynamo growth to occur.

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Abhik Basu. 2004-02-23. Dynamo mechanism: Effects of correlations and viscosities. https://doi.org/10.1140/epjb%2Fe2004-00107-0

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