A simplest A4 model for Tri-Bimaximal neutrino mixing

We present a see-saw A₄ model for Tri-Bimaximal mixing which is based on a very economical flavour symmetry and field content and still possesses all the good features of A₄ models. In particular the charged lepton mass hierarchies are determined by the A₄\ Z₄ flavour symmetry itself without invoking a Froggatt-Nielsen U (1) symmetry. Tri-Bimaximal mixing is exact in leading order while all the mixing angles receive corrections of the same order in next-to-the-leading approximation. As a consequence the predicted value of \₁₃ is within the sensitivity of the experiments which will take data in the near future. The light neutrino spectrum, typical of A₄ see-saw models, with its phenomenological implications, also including leptoproduction, is studied in detail.