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On the Fukugita-Tanimoto-Yanagida Ansatz with Partially Non-degenerate Right-handed Majorana Neutrinos

Midori Obara·Zhi-zhong Xing
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Abstract

Taking three right-handed Majorana neutrino masses $M^{}_i$ to be partially non-degenerate, we make a new analysis of the Fukugita-Tanimoto-Yanagida ansatz and confront it with current neutrino oscillation data. We determine the parameter space for cases (A) $M^{}_3 = M^{}_2 \neq M^{}_1$, (B) $M^{}_2 = M^{}_1 \neq M^{}_3$ and (C) $M^{}_1 = M^{}_3 \neq M^{}_2$, and examine their respective deviations from the original $M^{}_1 = M^{}_2 = M^{}_3$ case. The numerical constraints on three light neutrino masses, three neutrino mixing angles and three CP-violating phases are also obtained, together with the predictions for the Jarlskog invariant of CP violation and the effective masses of the tritium beta decay and the neutrinoless double-beta decay.

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Midori Obara, Zhi-zhong Xing. 2006-10-16. On the Fukugita-Tanimoto-Yanagida Ansatz with Partially Non-degenerate Right-handed Majorana Neutrinos. https://doi.org/10.1016/j.physletb.2006.11.010

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