Anatomy of RHN DM relic in the vanilla scotogenic neutrino mass model

TL;DR

This paper analyzes the right-handed neutrino dark matter relic in the minimal scotogenic model, considering various production mechanisms and experimental constraints, and explores potential collider signatures of long-lived particles.

Contribution

It provides a comprehensive study of RHN dark matter relics in the scotogenic model, including new insights into production processes and collider signatures.

Findings

Viable RHN DM mass range: 0.1 GeV to 2000 GeV.

Constraints from direct detection, colliders, and flavor violation.

Potential displaced vertex signatures at future colliders.

Abstract

The scotogeneic neutrino mass models are very popular choices to generate light neutrino masses via radiative mechanism. In these models, the particles running in the loop are distinguished from the standard model due to an imposed $\mathcal{Z}_2$ symmetry under which the loop particles are odd. Therefore, the lightest particle running in the loop can be a viable dark matter candidate. In this paper, we revisit the minimal scotogenic neutrino mass model and study the anatomy of right handed neutrino (RHN) DM relic, taking into account contributions from self-annihilation, co-annihilation, conversion-driven processes, as well as production via the freeze-in mechanism. We impose the constraints from direct detection and collider searches of DM including anomalous magnetic moment of muon, charged lepton flavor violation and low-energy neutrino oscillation data to show that the lightest RHN can be a viable DM in the mass range: $M_{h}/2\lesssim M_{\rm DM}\lesssim2000 {\rm GeV}$ (thermal DM) and $0.1 ~{\rm GeV}\lesssim M_{\rm DM}\lesssim 1000 {\rm GeV}$ (non-thermal DM), where $M_h$ denotes the Standard Model Higgs mass and $M_{\rm DM}$ is the RHN dark matter mass. We also find the displaced vertex signatures of long lived particles which can be probed at future colliders.