Deriving Models for keV sterile Neutrino Dark Matter with the Froggatt-Nielsen mechanism

TL;DR

This paper develops Froggatt-Nielsen-based models to explain the specific mass pattern of keV-scale sterile neutrinos as Warm Dark Matter, aligning with neutrino data and reducing charge assignment arbitrariness.

Contribution

It introduces a novel Froggatt-Nielsen framework that successfully models the unique mass hierarchy of sterile neutrinos while satisfying phenomenological constraints.

Findings

Models explain keV sterile neutrino mass pattern

Charge assignment constraints are significantly reduced

Analytical and numerical models demonstrate feasibility

Abstract

Sterile neutrinos with a mass around the keV scale are an attractive particle physics candidate for Warm Dark Matter. Although many frameworks have been presented in which these neutrinos can fulfill all phenomenological constraints, there are hardly any models known that can explain such a peculiar mass pattern, one sterile neutrino at the keV scale and the other two considerably heavier, while at the same time being compatible with low-energy neutrino data. In this paper, we present models based on the Froggatt-Nielsen mechanism, which can give such an explanation. We explain how to assign Froggatt-Nielsen charges in a successful way, and we give a detailed discussion of all conditions to be fulfilled. It turns out that the typical arbitrariness of the charge assignments is greatly reduced when trying to carefully account for all constraints. We furthermore present analytical calculations of a few simplified models, while quasi-perfect models are found numerically.