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arXiv · 1208.3666

What can we say about seed fields for galactic dynamos?

Dmitri Sokoloff·David Moss
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Abstract

We demonstrate that a quasi-uniform cosmological seed field is a much less suitable seed for a galactic dynamo than has often been believed. The age of the Universe is insufficient for a conventional galactic dynamo to generate a contemporary galactic magnetic field starting from such a seed, accepting conventional estimates for physical quantities. We discuss modifications to the scenario for the evolution of galactic magnetic fields implied by this result. We also consider briefly the implications of a dynamo number that is significantly larger than that given by conventional estimates.

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Dmitri Sokoloff, David Moss. 2012-08-17. What can we say about seed fields for galactic dynamos?. https://doi.org/10.1080/03091929.2011.649750

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