A possible symmetric neutrino mixing ansatz

Using a recent global analysis result after the precise measurement of θ13, a possible symmetric neutrino mixing ansatz is proposed, the mixing matrix is symmetric and also symmetric with respect to the second diagonal line in the leading order. This leading order ansatz predicts θ13=12.2°. Next, consider the hierarchy structure of the lepton mass matrix as the origin of perturbation of the mixing matrix, we find that this ansatz with perturbation can fit current data very well.