An extension of tribimaximal lepton mixing

Understand

Harrison, Perkins and Scott have proposed simple charged lepton and neutrino mass matrices that lead to the tribimaximal mixing $U_{\rm TBM}$.

• We consider in this work an extension of the mass matrices so that the leptonic mixing matrix becomes $U_{\rm PMNS}=V_L^{\ell\dagger}U_{\rm TBM}W$, where $V_L^\ell$ is a unitary matrix needed to diagonalize the charged lepton mass matrix and $W$ measures the deviation of the neutrino mixing matrix from the bimaximal form.
• Hence, corrections to $U_{\rm TBM}$ arise from both charged lepton and neutrino sectors.
• Following our previous work to assume a Qin-Ma-like parametrization $V_{\rm QM}$ for the charged lepton mixing matrix $V_L^\ell$ in which the {\it CP}-odd phase is approximately maximal, we study the phenomenological implications in two different scenarios: $V_L^\ell=V_{\rm QM}^\dagger$ and $V_L^\ell=V_{\rm QM}$.