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Universal Lepton Asymmetry: New Constraints from the Cosmic Microwave Background and Primordial Nucleosynthesis

T. Kajino·M. Orito·G. J. Mathews·R. N. Boyd
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Abstract

We study the primordial nucleosynthesis and cosmic age in the presence of a net lepton asymmetry as well as baryon asymmetry. We explore a previously unnoted region of the parameter space in which very large baryon densities $0.1 \le Ω_b \le 1$ can be accommodated within the light-element constraints from primordial nucleosynthesis. This parameter space consists of $ν_μ$ and $ν_τ$ degeneracies with a small $ν_e$ degeneracy. Constraints from cosmic microwave background fluctuations are also discussed (orito00).

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T. Kajino, M. Orito, G. J. Mathews, R. N. Boyd. 2002-02-06. Universal Lepton Asymmetry: New Constraints from the Cosmic Microwave Background and Primordial Nucleosynthesis. https://arxiv.org/abs/astro-ph/0202114

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