A Simple Motivated Completion of the Standard Model below the Planck Scale: Axions and Right-Handed Neutrinos

TL;DR

This paper proposes a minimal extension of the Standard Model incorporating right-handed neutrinos and axions, which simultaneously addresses neutrino masses, dark matter, baryon asymmetry, the strong CP problem, and electroweak vacuum stability.

Contribution

It introduces a simple, unified model that explains multiple beyond Standard Model phenomena within a single framework.

Findings

The model accounts for neutrino masses via type-I see-saw.

It provides a candidate for dark matter through axions.

It explains baryon asymmetry via leptogenesis.

Abstract

We study a simple Standard Model (SM) extension, which includes three families of right-handed neutrinos with generic non-trivial flavor structure and an economic implementation of the invisible axion idea. We find that in some regions of the parameter space this model accounts for all experimentally confirmed pieces of evidence for physics beyond the SM: it explains neutrino masses (via the type-I see-saw mechanism), dark matter, baryon asymmetry (through leptogenesis), solve the strong CP problem and has a stable electroweak vacuum. The last property may allow us to identify the Higgs field with the inflaton.