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arXiv · 0804.4055

Tri-bimaximal Mixing from Cascades

Naoyuki Haba·Ryo Takahashi·Morimitsu Tanimoto·Koichi Yoshioka
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Abstract

We study fermion mass matrices of the cascade form which are compatible with the tri-bimaximal lepton mixing and generation mass hierarchy. The flat-cascade lepton matrices imply a parameter-independent relation among the mixing angles and mass eigenvalues. The relation has several indications that the atmospheric neutrino mixing angle is close to maximal and the other two angles have a correlation independently of neutrino mass eigenvalues. We also discuss phenomenological aspects of the cascade matrices; flavor-violating rare decays of charged leptons, thermal leptogenesis, and leptonic CP violation. Possible dynamical origins of the cascades are illustrated based on flavor symmetry and in higher-dimensional theory.

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Naoyuki Haba, Ryo Takahashi, Morimitsu Tanimoto, Koichi Yoshioka. 2008-11-25. Tri-bimaximal Mixing from Cascades. https://doi.org/10.1103/physrevd.78.113002

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