Probing Lepton Asymmetry with 21 cm Fluctuations
Cosmology and Nongalactic Astrophysics
2016-02-09 v1 High Energy Physics - Phenomenology
Abstract
We investigate the issue of how accurately we can constrain the lepton number asymmetry xi_nu = mu_nu/T_nu in the Universe by using future observations of 21 cm line fluctuations and cosmic microwave background (CMB). We find that combinations of the 21 cm line and the CMB observations can constrain the lepton asymmetry better than big-bang nucleosynthesis (BBN). Additionally, we also discuss constraints on xi_nu in the presence of some extra radiation, and show that the 21 cm line observations can substantially improve the constraints obtained by CMB alone, and allow us to distinguish the effects of the lepton asymmetry from the ones of extra radiation.
Keywords
Cite
@article{arxiv.1404.4847,
title = {Probing Lepton Asymmetry with 21 cm Fluctuations},
author = {Kazunori Kohri and Yoshihiko Oyama and Toyokazu Sekiguchi and Tomo Takahashi},
journal= {arXiv preprint arXiv:1404.4847},
year = {2016}
}
Comments
22 pages, 4 figures