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arXiv · hep-ph/9907390

Neutrino Anomalies in an Extended Zee Model

Anjan S. Joshipura·Saurabh D. Rindani
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Abstract

We discuss an extended $SU(2)\times U(1)$ model which naturally leads to mass scales and mixing angles relevant for understanding both the solar and atmospheric neutrino anomalies. No right-handed neutrinos are introduced in the model.The model uses a softly broken $L_e-L_μ-L_τ$ symmetry. Neutrino masses arise only at the loop level. The one-loop neutrino masses which arise as in the Zee model solve the atmospheric neutrino anomaly while breaking of $L_e-L_μ-L_τ$ generates at two-loop order a mass splitting needed for the vacuum solution of the solar neutrino problem. A somewhat different model is possible which accommodates the large-angle MSW resolution of the solar neutrino problem.

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Anjan S. Joshipura, Saurabh D. Rindani. 1999-07-30. Neutrino Anomalies in an Extended Zee Model. https://doi.org/10.1016/s0370-2693(99)00995-8

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