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arXiv · hep-ph/9608308

Baryon Asymmetry and Neutrino Mixing

W. Buchmuller·M. Plumacher
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Abstract

In theories where $B-L$ is a spontaneously broken local symmetry, the cosmological baryon asymmetry can be generated by the out-of-equilibrium decay of heavy Majorana neutrinos. We study this mechanism assuming a similar pattern of mixings and masses for leptons and quarks, as suggested by SO(10) unification. This implies that $B-L$ is broken at the unification scale $Λ_{\mbox{\scriptsize GUT}}\sim 10^{16}$ GeV, if $m_{\n_\m} \sim 3\cdot 10^{-3}$eV as preferred by the MSW explanation of the solar neutrino deficit. The observed value of the baryon asymmetry, $n_B/s \sim 10^{-10}$, is then obtained without any fine tuning of parameters.

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W. Buchmuller, M. Plumacher. 1996-08-13. Baryon Asymmetry and Neutrino Mixing. https://doi.org/10.1016/s0370-2693(96)01232-4

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