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The First Magnetic Fields

George Davies·Lawrence M. Widrow
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Abstract

We demonstrate that the Biermann battery mechanism for the creation of large scale magnetic fields can arise in a simple model protogalaxy. Analytic calculations and numerical simulations follow explicitly the generation of vorticity (and hence magnetic field) at the outward-moving shock that develops as the protogalactic perturbation collapses. Shear angular momentum then distorts this field into a dipole-like configuration. The magnitude of the field created in the fully formed disk galaxy is estimated to be 10^(-17) Gauss, approximately what is needed as a seed for the galactic dynamo.

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George Davies, Lawrence M. Widrow. 1999-12-14. The First Magnetic Fields. https://arxiv.org/abs/astro-ph/9912260

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