Multiple seesaw mechanisms of neutrino masses at the TeV scale

TL;DR

This paper introduces two novel classes of multiple seesaw mechanisms at the TeV scale, extending canonical models to explain tiny neutrino masses with potential testability at colliders and neutrino experiments.

Contribution

It proposes new multiple seesaw models with specific symmetry implementations, providing a framework for TeV-scale neutrino mass generation beyond existing mechanisms.

Findings

Neutrino mass matrices exhibit a nearest-neighbor-interaction pattern.

Models are testable at the LHC and neutrino experiments.

A simple example of model building illustrates the approach.

Abstract

In pursuit of a balance between theoretical naturalness and experimental testability, we propose two classes of multiple seesaw mechanisms at the TeV scale to understand the origin of tiny neutrino masses. They are novel extensions of the canonical and double seesaw mechanisms, respectively, by introducing even and odd numbers of gauge-singlet fermions and scalars. It is thanks to a proper implementation of the global U(1)xZ_2N symmetry that the overall neutrino mass matrix in either class has a suggestive nearest-neighbor-interaction pattern. We briefly discuss possible consequences of these TeV-scale seesaw scenarios, which can hopefully be explored in the upcoming Large Hadron Collider and precision neutrino experiments, and present a simple but instructive example of model building.