Tri-bimaximal-Cabibbo Mixing

Recent measurements of the lepton mixing angle θ13 by the Daya Bay and RENO reactor experiments are consistent with the relationship θ13 ≈ θC/ √ 2 where θC is the Cabibbo angle. We propose Tri-bimaximal-Cabibbo (TBC) mixing, in which sin θ13 = sin θC/ √ 2, sin θ23 = 1/ √ 2 and sin θ12 = 1/ √ 3. We show that TBC mixing may arise approximately from Tri-bimaximal, Bi-maximal or Golden Ratio neutrino mixing, together with Cabibbo-like charged lepton corrections arising from a Pati-Salam gauge group, leading to predictions for the CP-violating phase of δ ≈ ±90o,±180o,±75o, respectively. Alternatively, we show that TBC neutrino mixing may realised accurately using the type I see-saw mechanism with partially constrained sequential right-handed neutrino dominance, assuming a family symmetry which is broken by a flavon common to quarks and neutrinos. E-mail: [email protected]