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arXiv · hep-ph/9603201

Nucleosynthesis and the mass of the tau neutrino

Steen Hannestad·Jes Madsen
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Abstract

The primordial abundance of long-lived heavy Majorana neutrinos is calculated from the full Boltzmann equation. Inclusion of scattering reactions drastically change the predicted abundance of a heavy neutrino species. This loosens the well known mass constraint on MeV neutrinos from Big Bang nucleosynthesis, and allows for the existence of a Majorana tau neutrino with mass m > 11 MeV. Further experimental efforts are therefore needed to investigate the range 11 MeV < m < 24 MeV. Some interesting cosmological consequences of an MeV nu_tau are also pointed out.

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Steen Hannestad, Jes Madsen. 1996-03-01. Nucleosynthesis and the mass of the tau neutrino. https://doi.org/10.1103/physrevlett.76.2848

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