Cosmological constraints on thermal relic axions and axion-like particles
arXiv:1110.5837 · doi:10.1088/1742-6596/375/1/022002
Abstract
Cosmological precision data can be used to set very strict constraints on Axions and Axion-like particles (ALPs) produced thermally in the big bang. We briefly review the known bounds and propose two new constraints for Axions and ALPs decaying in the early universe, based upon the concomitant dilution of baryon and neutrino densities, using WMAP7 and other cosmological data.
4 pages, 4 figures. To appear in the proceedings of 7th Patras Workshop on Axions, WIMPs and WISPs, Mykonos, Greece, 26 June - 1 July 2011 and of TAUP 2011, Munich, Germany, 5 - 9 September 2011