Predictions for the neutrino parameters in the minimal gauged $$\hbox {U}(1)_{L_\mu -L_\tau }$$ U ( 1 ) L μ - L τ model

Abstract

We study the structure of the neutrino-mass matrix in the minimal gauged U(1) L μ −L τ model, where three right-handed neutrinos are added to the Standard Model in order to obtain non-zero masses for the active neutrinos. Because of the U(1) L μ −L τ gauge symmetry, the structure of both Dirac and Majorana mass terms of neutrinos is tightly restricted. In particular, the inverse of the neutrinomass matrix has zeros in the (μ, μ) and (τ, τ ) components, namely, this model offers a symmetric realization of the socalled two-zero-minor structure in the neutrino-mass matrix. Due to these constraints, all the CP phases -the Dirac CP phase δ and the Majorana CP phases α 2 and α 3 -as well as the mass eigenvalues of the light neutrinos m i are uniquely determined as functions of the neutrino mixing angles θ 12 , θ 23 , and θ 13 , and the squared mass differences m 2 21 and m 2 31 . We find that this model predicts the Dirac CP phase δ to be δ 1.59π -1.70π (1.54π -1.78π ), the sum of the neutrino masses to be i m i 0.14-0.22 eV (0.12-0.40 eV), and the effective mass for the neutrinoless double-beta decay to be m ββ 0.024-0.055 eV (0.017-0.12 eV) at 1σ (2σ ) level, which are totally consistent with the current experimental limits. These predictions can soon be tested in future neutrino experiments. Implications for leptogenesis are also discussed.

Self-interacting dark matter and muon (g − 2) in a gauged $$ \mathrm{U}{(1)}_{L_{\mu }-{L}_{\tau }} $$ model

“…In addition, the observation of a nearby supernova may also provide important hints on the properties of Z , since the non-standard neutrino selfinteraction shortens the mean free path and increases the neutrino diffusion time from the supernova core [48]. On the model building aspect, we could introduce three right-handed neutrinos and realize the see-saw mechanism to reproduce the observed neutrino masses and mixings [73].…”

Predictions for the neutrino parameters in the minimal model extended by linear combination of U(1)$$_{L_e-L_\mu }$$, U(1)$$_{L_\mu -L_\tau }$$ and U(1)$$_{B-L}$$ gauge symmetries

“…For previous studies on the neutrino sector of the gauged U(1) L α −L β models, see Refs. [56][57][58][59][60][61][62][63][64][65][66]. In Refs.…”

“…In Refs. [64,65], we have discussed them in detail, and have given the predictions for unknown parameters, such as the CP phases, the neutrino masses, and the effective neutrino mass, in the case of the minimal extended model by a U(1) L α −L β gauge symmetry, that we call "the minimal gauged U(1) L α −L β model", and we have found that these models are already ruled out or are driven into a corner.…”

Flavor non-universal gauge interactions and anomalies in B-meson decays

“…Some models have been discussed in Refs. [60][61][62][63]. In general, we can have the charge assignment as in Table I, where a, b, c, d, e and f are arbitrary real numbers but satisfy…”