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arXiv · hep-ph/0309050

Maximal atmospheric neutrino mixing and the small ratio of muon to tau mass

W. Grimus·L. Lavoura
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Abstract

We discuss the problem of the small ratio of muon mass to tau mass in a class of seesaw models where maximal atmospheric neutrino mixing is enforced through a $μ$--$τ$ interchange symmetry. We introduce into those models an additional symmetry $T$ such that $m_μ= 0$ in the case of exact $T$ invariance. The symmetry $T$ may be softly broken in the Higgs potential, and one thus achieves $m_μ\ll m_τ$ in a technically natural way. We speculate on a wider applicability of this mechanism.

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W. Grimus, L. Lavoura. 2003-11-17. Maximal atmospheric neutrino mixing and the small ratio of muon to tau mass. https://doi.org/10.1088/0954-3899%2F30%2F2%2F007

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