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Can the Lepton Flavor Mixing Matrix Be Symmetric?

Zhi-zhong Xing
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Abstract

Current neutrino oscillation data indicate that the 3x3 lepton flavor mixing matrix V is likely to be symmetric about its V_{e3}-V_{μ2}-V_{τ1} axis. This off-diagonal symmetry corresponds to three pairs of {\it congruent} unitarity triangles in the complex plane. Terrestrial matter effects can substantially modify the genuine CP-violating parameter and off-diagonal asymmetries of V in realistic long-baseline experiments of neutrino oscillations.

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Zhi-zhong Xing. 2002-06-26. Can the Lepton Flavor Mixing Matrix Be Symmetric?. https://doi.org/10.1103/physrevd.65.113010

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