Confronting minimal freeze-in models with the LHC

TL;DR

This paper explores a class of freeze-in dark matter models where long-lived charged particles decay into dark matter, and analyzes how current LHC searches constrain these models and what potential discoveries could reveal about early universe conditions.

Contribution

The paper introduces a new class of freeze-in dark matter models with long-lived parent particles and evaluates their collider signatures and constraints from LHC data.

Findings

Collider searches significantly constrain the models.

Observation could provide insights into reheating temperature.

Models remain viable within current experimental bounds.

Abstract

We present a class of dark matter models, in which the dark matter particle is a feebly interacting massive particle (FIMP) produced via the decay of an electrically charged and/or colored parent particle. Given the feeble interaction, dark matter is produced via the freeze-in mechanism and the parent particle is long-lived. The latter leads to interesting collider signatures. We study current LHC constrains on our models arising from searches for heavy charged particles, disappearing tracks, displaced leptons and displaced vertices. We demonstrate not only that collider searches can be a powerful probe of the freeze-in dark matter models under consideration, but that an observation can lead as well to interesting insights on the reheating temperature and thus on the validity of certain baryogenesis models.