English

The First Magnetic Fields

Astrophysics 2007-05-23 v1

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.

Keywords

Cite

@article{arxiv.astro-ph/9912260,
  title  = {The First Magnetic Fields},
  author = {George Davies and Lawrence M. Widrow},
  journal= {arXiv preprint arXiv:astro-ph/9912260},
  year   = {2007}
}

Comments

14 pages of text, 1 table, 8 figures