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Flavor Democracy and Type-II Seesaw Realization of Bilarge Neutrino Mixing

Werner Rodejohann·Zhi-zhong Xing
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Abstract

We generalize the democratic neutrino mixing Ansatz by incorporating the type-II seesaw mechanism with S(3) flavor symmetry. We find that bilarge neutrino mixing can naturally appear if the flavor democracy contribution is strongly suppressed due to significant cancellation between the conventional seesaw and triplet mass terms. Explicit S(3) symmetry breaking yields successful neutrino phenomenology and various testable correlations between the neutrino mass and mixing parameters. Among the results are a normal neutrino mass ordering, $0.005 \le |U_{e3}| \le 0.057$, $1 - \sin^2 2θ_{23} \ge 0.005$, positive $J_{\rm CP}$ and moderate cancellation in the effective mass of the neutrinoless double beta decay.

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Werner Rodejohann, Zhi-zhong Xing. 2004-09-28. Flavor Democracy and Type-II Seesaw Realization of Bilarge Neutrino Mixing. https://doi.org/10.1016/j.physletb.2004.09.061

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