Tri-bimaximal Neutrino Mixing and Its Viable Variations
نویسندگان
چکیده
Current experimental data allow the zero value for one neutrino mass, either m1 = 0 or m3 = 0. This observation implies that a realistic neutrino mass texture can be established by starting from the limit (a) m1 = m2 = 0 and m3 6= 0 or (b) m1 = m2 6= 0 and m3 = 0. In both cases, we may introduce a particular perturbation which ensures the resultant neutrino mixing matrix to be the tri-bimaximal mixing pattern or its viable variations with all entries being formed from small integers and their square roots. We illustrate that such neutrino mass matrices can easily be derived from the minimal seesaw model with two heavy right-handed Majorana neutrinos. We also point out a simple possibility of generalizing this phenomenological ansatz to obtain sin 2θ13 ≈ 2me/mμ ≈ 0.01 and leptonic CP violation.
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