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arXiv · hep-ph/9508275

Reconciling sterile neutrinos with big bang nucleosynthesis

R. Foot·R. R. Volkas
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Abstract

We re-examine the big bang nucleosynthesis (BBN) bounds on the mixing of neutrinos with sterile species. These bounds depend on the assumption that the relic neutrino asymmetry $L_ν$ is very small. We show that for $L_ν$ large enough (greater than about $10^{-5}$) the standard BBN bounds do not apply. We apply this result to the sterile neutrino solution to the atmospheric neutrino anomaly and show that for $L_ν > 7 \times 10^{-5}$ it is consistent with BBN. The BBN bounds on sterile neutrinos mixing with electron neutrinos can also be weakened considerably.

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R. Foot, R. R. Volkas. 1995-11-08. Reconciling sterile neutrinos with big bang nucleosynthesis. https://doi.org/10.1103/physrevlett.75.4350

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