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arXiv · 0805.1175

A light pseudoscalar in a model with lepton family symmetry O(2)

W. Grimus·L. Lavoura·D. Neubauer
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Abstract

We discuss a realization of the non-abelian group O(2) as a family symmetry for the lepton sector. The reflection contained in O(2) acts as a mu-tau interchange symmetry, enforcing--at tree level--maximal atmospheric neutrino mixing and a vanishing mixing angle theta_13. The small ratio m_mu/m_tau (muon over tau mass) gives rise to a suppression factor in the mass of one of the pseudoscalars of the model. We argue that such a light pseudoscalar does not violate any experimental constraint.

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W. Grimus, L. Lavoura, D. Neubauer. 2008-06-24. A light pseudoscalar in a model with lepton family symmetry O(2). https://doi.org/10.1088/1126-6708%2F2008%2F07%2F051

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