Lepton seesaw model in a modular $A_4$ symmetry

TL;DR

This paper introduces a lepton mass model using modular $A_4$ symmetry, combining seesaw and inverse seesaw mechanisms, and analyzes fixed points in string theory compactification for viable solutions.

Contribution

It presents a novel lepton mass model employing modular $A_4$ symmetry with combined seesaw mechanisms and explores fixed points in string theory for realistic predictions.

Findings

Good solutions found near $ au=\omega$ with specific predictions.

Mass matrices derived via combined seesaw and inverse seesaw mechanisms.

Model aligns with flux compactification fixed points in string theory.

Abstract

We propose a lepton seesaw model to get the same mass-origin of charged-leptons and neutrinos introducing a modular $A_4$ symmetry. In this scenario, the mass matrix of charged-leptons is induced via seesaw-like mechanism while the mass matrix of neutrino is realized via an inverse seesaw mechanism with help of vector-like fermions and an isospin singlet and triplet scalar field with nonzero vacuum expectation values. In analyzing the model we concentrate on fixed points of modulus $\tau$ that is favored by a flux compactification of Type IIB string theory. We search for allowed region at nearby these fixed points and find good solutions at nearby $\tau=\omega$ with several good predictions.