Radiative Neutrino Mass with $Z_3$ Dark matter: From Relic Density to LHC Signatures

TL;DR

This paper explores a $ ext{Z}_3$ dark matter model where neutrino masses are generated at two loops, analyzing relic density, detection prospects, and LHC signatures, highlighting semi-annihilation effects and collider signals.

Contribution

It provides a comprehensive phenomenological analysis of a $ ext{Z}_3$ dark matter model with neutrino mass generation, including relic density, detection, and collider signatures, with novel decay channels and semi-annihilation effects.

Findings

Semi-annihilation and co-annihilation are key in relic density and detection.

Distinct LHC signals from $ ext{Z}_3$ particles, especially trilepton signatures.

Fermion dark matter signatures resemble electroweakinos in supersymmetry.

Abstract

In this work we give a comprehensive analysis on the phenomenology of a specific $\mathbb{Z}_3$ dark matter (DM) model in which neutrino mass is induced at two loops by interactions with a DM particle that can be a complex scalar or a Dirac fermion. Both the DM properties in relic density and direct detection and the LHC signatures are examined in great detail, and indirect detection for gamma-ray excess from the Galactic Center is also discussed briefly. On the DM side, both semi-annihilation and co-annihilation processes play a crucial role in alleviating the tension of parameter space between relic density and direct detection. On the collider side, new decay channels resulting from $\mathbb{Z}_3$ particles lead to distinct signals at LHC. Currently the trilepton signal is expected to give the most stringent bound for both scalar and fermion DM candidates, and the signatures of fermion DM are very similar to those of electroweakinos in simplified supersymmetric models.