CPviolation in bilarge lepton mixing

Abstract

We propose a scheme of lepton mixing in which the unitary matrix that diagonalizes the neutrino mass matrix is bimaximal and the deviation from the bimaximal of the lepton mixing matrix is due to the unitary matrix that diagonalizes the charged-lepton mass matrix. This matrix is assumed to be hierarchical, like the quark mixing matrix. It is shown that in general it is possible to have a sizable value for $|{U}_{e3}|$ together with an effective two-neutrino maximal mixing in solar neutrino experiments. If the effective mixing in solar neutrino experiments is less than maximal, as indicated by current data, $|{U}_{e3}|$ is bounded from below. Furthermore, in general the violation of $\mathrm{CP}$ could be relatively large.