Tri-bimaximal-Cabibbo Mixing

TL;DR

This paper introduces Tri-bimaximal-Cabibbo (TBC) mixing, a new neutrino mixing pattern consistent with recent experimental data, derived from existing mixing schemes and specific charged lepton corrections, with implications for CP violation.

Contribution

The paper proposes the TBC mixing pattern, connecting neutrino mixing angles with the Cabibbo angle, and provides models explaining its origin via charged lepton corrections and the see-saw mechanism.

Findings

TBC mixing predicts specific CP-violating phases.

TBC mixing aligns with recent measurements of $ heta_{13}$.

Models based on family symmetry and see-saw mechanism support TBC.

Abstract

Recent measurements of the lepton mixing angle $\theta_{13}$ by the Daya Bay and RENO reactor experiments are consistent with the relationship $\theta_{13}\approx \theta_C/\sqrt{2}$ where $ \theta_C$ is the Cabibbo angle. We propose Tri-bimaximal-Cabibbo (TBC) mixing, in which $\sin \theta_{13}= \sin \theta_C/\sqrt{2}$, $\sin \theta_{23}= 1/\sqrt{2}$ and $\sin \theta_{12}= 1/\sqrt{3}$. 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 $\delta \approx \pm 90^o, \pm 180^o, \pm 75^o$, 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.