A4-based tri-bimaximal mixing within inverse and linear seesaw schemes

TL;DR

This paper explores tri-bimaximal lepton mixing in low-scale inverse and linear seesaw models with A4 flavor symmetry, predicting neutrino properties, neutrinoless double beta decay bounds, and lepton flavor violation rates.

Contribution

It introduces highly predictive inverse and linear seesaw models with A4 symmetry, linking neutrino mixing, neutrinoless double beta decay, and lepton flavor violation.

Findings

Linear seesaw predicts a lower bound for neutrinoless double beta decay.

Both models depend on only three mass parameters and one Majorana phase.

Models suggest potentially observable lepton flavor violating processes.

Abstract

We consider tri-bimaximal lepton mixing within low-scale seesaw schemes where light neutrino masses arise from TeV scale physics, potentially accessible at the Large Hadron Collider (LHC). Two examples are considered, based on the A4 flavor symmetry realized within the inverse or the linear seesaw mechanisms. Both are highly predictive so that in both the light neutrino sector effectively depends only on three mass parameters and one Majorana phase, with no CP violation in neutrino oscillations. We find that the linear seesaw leads to a lower bound for neutrinoless double beta decay while the inverse seesaw does not. The models also lead to potentially sizeable decay rates for lepton flavor violating processes, tightly related by the assumed flavor symmetry.