Mass problem in the Standard Model

TL;DR

This paper introduces a new gauge model extending the Standard Model with an additional U(1) symmetry, incorporating extra fermions and neutrino mass mechanisms, and analyzes neutrino oscillation data to constrain model parameters.

Contribution

It proposes a novel non-universal gauge extension with extra fermions and neutrino masses, providing mass ansatzes and fitting neutrino oscillation data.

Findings

Allowed regions for Yukawa couplings consistent with neutrino oscillation data.

Mass ansatzes for leptons and quarks within the new gauge framework.

Compatibility with normal and inverted neutrino mass hierarchies.

Abstract

We propose a new $\mathrm{SU}(3)_C \otimes \mathrm{SU}(2)_{L}\otimes \mathrm{U}(1)_{Y}\otimes \mathrm{U}(1)_{X}$ gauge model which is non universal respect to the three fermion families of the Standard Model. We introduce additional one top-like quark, two bottom-like quarks and three right handed neutrinos in order to have an anomaly free theory. We also consider additional three right handed neutrinos which are singlets respect to the gauge symmetry of the model to implement see saw mechanism and give masses to the light neutrinos according to the neutrino oscillation phenomenology. In the context of this horizontal gauge symmetry we find mass ansatz for leptons and quarks. In particular, from the analysis of solar, atmospheric, reactor and accelerator neutrino oscillation experiments, we get the allow region for the Yukawa couplings for the charge and neutral lepton sectors according with the mass squared differences and mixing angles for the two neutrino hierarchy schemes, normal and inverted.