Probing the scotogenic FIMP at the LHC

TL;DR

This paper investigates the collider signatures of a scotogenic model with a feebly interacting dark matter candidate produced via freeze-in, focusing on potential LHC signals and current experimental bounds.

Contribution

It provides a detailed analysis of LHC signatures for the scotogenic FIMP model, including decay-length predictions and parameter bounds based on current searches.

Findings

Potential macroscopic decay lengths for next-to-lightest particles.

Characterization of LHC signals depending on the particle spectrum.

Derived bounds on model parameters from existing LHC data.

Abstract

We analyse the signatures at the Large Hadron Collider (LHC) of the scotogenic model, when the lightest Z2-odd particle is a singlet fermion and a feebly interacting massive particle (FIMP). We further assume that the singlet fermion constitutes the dark matter and that it is produced in the early Universe via the freeze-in mechanism. The small couplings required to reproduce the observed dark matter abundance translate into decay-lengths for the next-to-lightest Z2-odd particle which can be macroscopic, potentially leading to spectacular signatures at the LHC. We characterize the possible signals of the model according to the spectrum of the Z2-odd particles and we derive, for each of the cases, bounds on the parameters of the model from current searches.