Viability of the exact tri-bimaximal mixing at M_{GUT} in SO(10)

TL;DR

This paper investigates the possibility of maintaining exact tri-bimaximal leptonic mixing at the GUT scale within an SO(10) model, fitting fermion masses and mixing angles, and analyzing perturbations related to recent experimental results.

Contribution

It demonstrates that exact tri-bimaximal mixing can be achieved at the GUT scale in an SO(10) model while fitting all fermion masses and mixing angles.

Findings

Excellent fits to fermion masses and quark mixing angles are possible.

Certain perturbations can explain recent T2K and MINOS results.

Some perturbations cannot account for the observed reactor mixing angle.

Abstract

General structures of the charged lepton and the neutrino mixing matrices leading to tri-bimaximal leptonic mixing are determined. These are then integrated into an SO(10) model within which detailed fits to fermion masses and mixing angles are given. It is shown that one can obtain excellent fits to all the fermion masses and quark mixing angles keeping tri-bimaximal leptonic mixing intact. Different perturbations to the basic structure are considered and those which can or which cannot account for the recent T2K and MINOS results on the reactor mixing angle $\theta_{13}^l$ are identified.