Cosmological constraints on axionic dark radiation from axion-photon conversion in the early Universe
High Energy Physics - Phenomenology
2015-06-16 v2 Cosmology and Nongalactic Astrophysics
High Energy Physics - Theory
Abstract
Axions seem ubiquitous in string theories and some of them may be produced non-thermally by heavy scalar decays, contributing to dark radiation. We study various cosmological effects of photons produced from the axionic dark radiation through axion-photon conversion in the presence of primordial magnetic fields, and derive tight constraints on the combination of the axion-photon coupling and the primordial magnetic field.
Keywords
Cite
@article{arxiv.1306.6518,
title = {Cosmological constraints on axionic dark radiation from axion-photon conversion in the early Universe},
author = {Tetsutaro Higaki and Kazunori Nakayama and Fuminobu Takahashi},
journal= {arXiv preprint arXiv:1306.6518},
year = {2015}
}
Comments
24 pages, 4 figures; references added, minor corrections; to appear in JCAP