A shift from democratic to tri-bimaximal neutrino mixing with relatively large θ13

Recent neutrino oscillation data hint that the smallest neutrino mixing angle theta(13) is possible to lie in the range 5 degrees less than or similar to theta(13) less than or similar to 12 degrees. We show that reasonable perturbations to the democratic mixing pattern, which is geometrically related to the tri-bimaximal mixing pattern through an equal shift theta(*) similar or equal to 9.7 degrees of two large mixing angles, can naturally produce a nearly tri-bimaximal neutrino mixing matrix V with sufficiently large theta(13). Two especially simple but viable scenarios of V are proposed and their phenomenological consequences are discussed. (C) 2010 Elsevier B.V. All rights reserved.