Intrinsic deviation from the tri-bimaximal neutrino mixing in a class of A4 flavor models

It is well known that the tri-bimaximal neutrino mixing pattern V-0 can be derived from a class of flavor models with the non-Abelian A(4) symmetry. We point out that small corrections to V-0, which are inherent in the A(4) models and arise from both the charged-lepton and neutrino sectors, have been omitted in the previous works. We show that such corrections may lead the 3 x 3 neutrino mixing matrix V to a non-unitary deviation from V-0, but they cannot result in a nonzero value of theta(13) or any new CF-violating phases. Current experimental constraints on the unitarity of V allow us to constrain the model parameters to some extent. (C) 2010 Elsevier B.V. All rights reserved.