Generation of large scale magnetic fields at recombination epoch

Z. Berezhiani; A. D. Dolgov

doi:10.1016/j.astropartphys.2003.11.002

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arXiv · astro-ph/0305595

Generation of large scale magnetic fields at recombination epoch

Z. Berezhiani·A. D. Dolgov

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Abstract

It is argued that large scale cosmic magnetic field could be generated in the primeval plasma slightly before hydrogen recombination. Non-zero vorticity, necessary for that, might be created by the photon diffusion in the second order in the temperature fluctuations. The resulting seed fields at galactic scale would be only 4 orders of magnitude smaller than the observed ones and with a mild galactic dynamo amplifying the seed fields by the factor $\sim 10^4$ an existence of coherent magnetic fields in galaxies may be explained.

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Z. Berezhiani, A. D. Dolgov. 2003-06-17. Generation of large scale magnetic fields at recombination epoch. https://doi.org/10.1016/j.astropartphys.2003.11.002

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