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Consequences of a Z_2 Symmetry for Neutrino Oscillation

C. S. Lam
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Abstract

A $Z_{2L}\times Z_{2R}$ generation symmetry in the neutrino sector predicts the atmospheric neutrino mixing to be maximal, and the MNS matrix element $U_{e3}$ to be zero, consistent with observations. Solar neutrino mixing may be maximal but is not required by the symmetry. Neutrino masses of the first two generations are predicted to vanish, providing a first approximation to the oscillation data. The consequence of a smaller $Z_2$ symmetry is also discussed. In that case, deviation from the $Z_{2L}\times Z_{2R}$ result is of the order of the neutrino mass ratio between the first two generations and the third generation.

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C. S. Lam. 2000-08-18. Consequences of a Z_2 Symmetry for Neutrino Oscillation. https://arxiv.org/abs/hep-ph/0008203

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