A Note on the Cosmic Evolution of the Axion in a Strong Magnetic Field
Astrophysics
2009-11-13 v2
Abstract
It has been pointed out in the literature that in the presence of an external magnetic field the axion mass receives an electromagnetic contribution. We show that if a magnetic field with energy density larger than ~10^{-8} times the energy density of the Universe existed at temperatures of a few GeV, that contribution would be dominant and consequently the cosmic evolution of the axion field would change substantially. In particular, the expected axion relic abundance would be lowered, allowing a small relaxation of the present cosmological bound on the Peccei-Quinn constant.
Cite
@article{arxiv.astro-ph/0512324,
title = {A Note on the Cosmic Evolution of the Axion in a Strong Magnetic Field},
author = {L. Campanelli and M. Giannotti},
journal= {arXiv preprint arXiv:astro-ph/0512324},
year = {2009}
}
Comments
2 pages, no figures. Minor changes. References added. Accepted for publication in JCAP