Journal
EPL
Volume 119, Issue 2, Pages -Publisher
IOP Publishing Ltd
DOI: 10.1209/0295-5075/119/29001
Keywords
-
Categories
Funding
- Studienstiftung des Deutschen Volkes
- DFG [RTG 1620]
Ask authors/readers for more resources
A cosmic lepton asymmetry eta(1) = (n(1) - n((1) over bar))/n(gamma) affects the primordial helium abundance and the expansion rate of the early Universe. Both of these effects have an impact on the anisotropies of the cosmic microwave background (CMB). We derive constraints on the neutrino chemical potentials from the Planck 2015 data, assuming equal lepton flavour asymmetries and negligible neutrino masses. We find xi = -0.002(-0.111)(+0.114) (95% CL) for the chemical potentials, which corresponds to -0.085 <= eta(1) <= 0.084. Our constraints on the lepton asymmetry are significantly stronger than previous constraints from CMB data analysis and we argue that they are more robust than those from primordial light element abundances. The resulting constraints on the primordial helium and deuterium abundances are consistent with those from direct measurements. Copyright (C) EPLA, 2017
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available