Revisiting the A₄ model for leptons in light of NuFIT 3.2

We revisit the A₄ model for leptons in light of the new result of NuFIT 3.2. We introduce a new flavon η transforming as an A₄ singlet 1' or 1", which couples to both charged leptons and neutrinos in next-to-leading-order operators. The model consists of five parameters: The lightest neutrino mass m1, the vacuum expectation value of η, and three CP-violating phases after inputting the experimental values of Δm² _atm and Δm²sol. The model with the 1" singlet flavon gives the prediction of sin² θ₁₂ around the best fit of NuFIT 3.2 while staying near the maximal mixing of θ₂₃. Inputting the experimental mixing angles with the 1σ error-bar, the Dirac CPviolating phase is clearly predicted to be |δ_CP| = 50-120°, which will be tested by the precise observed value in the future. In order to get the best-fit value sin² θ₂₃ = 0.538, the sum of three neutrino masses is predicted to be larger than 90 meV. The cosmological observation for the sum of the neutrino masses will also provide a crucial test of our predictions. It is remarked that the model is consistent with the experimental data only for the normal hierarchy of neutrino masses.