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arXiv · 0804.4897

Non-unitary deviation from the tri-bimaximal lepton mixing and its implications on neutrino oscillations

Shu Luo
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Abstract

We propose a new pattern of the neutrino mixing matrix which can be parametrized as the product of an arbitrary Hermitian matrix and the well-known tri-bimaximal mixing matrix. In this scenario, nontrivial values of the smallest neutrino mixing angle θ_13 and the CP-violating phases entirely arise from the non-unitary corrections. We present a complete set of series expansion formulas for neutrino oscillation probabilities both in vacuum and in matter of constant density. We do a numerical analysis to show the non-unitary effects on neutrino oscillations. The possibility of determining small non-unitary perturbations and CP-violating phases is discussed by measuring neutrino oscillation probabilities and constructing "deformed unitarity triangles". Some brief comments on the non-unitary neutrino mixing matrix in the type-II seesaw models are also given.

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Shu Luo. 2008-07-05. Non-unitary deviation from the tri-bimaximal lepton mixing and its implications on neutrino oscillations. https://doi.org/10.1103/physrevd.78.016006

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