Tri-bimaximal Neutrino Mixing from A(4) and \theta_{13} \sim \theta_C

Understand

It is a common believe that, if the Tri-bimaximal mixing (TBM) pattern is explained by vacuum alignment in an A(4) model, only a very small reactor angle, say \theta_{13} \sim \lambda^2_C being \lambda_C \equiv \theta_C the Cabibbo angle, can be accommodated.

• This statement is based on the assumption that all the flavon fields acquire VEVs at a very similar scale and the departures from exact TBM arise at the same perturbation level.
• From the experimental point of view, however, a relatively large value \theta_{13} \sim \lambda_C is not yet excluded by present data.
• In this paper, we propose a Seesaw A(4) model in which the previous assumption can naturally be evaded.