Generic Friedberg-Lee Symmetry of Dirac Neutrinos

TL;DR

This paper explores a Dirac neutrino mass model with Friedberg-Lee symmetry, showing that symmetry breaking leads to a nearly tri-bimaximal mixing pattern consistent with current experimental data and favoring a normal mass hierarchy.

Contribution

It introduces a generic Dirac neutrino mass operator with Friedberg-Lee symmetry and demonstrates how symmetry breaking yields realistic neutrino mixing consistent with experiments.

Findings

Neutrino mass matrix is asymmetric under FL symmetry.

Breaking FL symmetry results in nearly tri-bimaximal mixing.

Model favors the normal neutrino mass hierarchy.

Abstract

We write out the generic Dirac neutrino mass operator which possesses the Friedberg-Lee (FL) symmetry and find that its corresponding neutrino mass matrix is asymmetric. Following a simple way to break the FL symmetry, we calculate the neutrino mass eigenvalues and show that the resultant neutrino mixing pattern is nearly tri-bimaximal. Imposing the Hermitian condition on the neutrino mass matrix, we also show that the simplified ansatz is consistent with current experimental data and favors the normal neutrino mass hierarchy.