Interplay of super-WIMP and freeze-in production of dark matter

TL;DR

This paper explores how non-thermal dark matter can be produced through both freeze-in and superWIMP mechanisms, analyzing their interplay and collider implications within a specific mediator model.

Contribution

It provides a comprehensive analysis of the combined freeze-in and superWIMP production mechanisms for dark matter, including collider and cosmological constraints.

Findings

Mapped the parameter space considering collider, BBN, and Lyman-alpha bounds.

Identified regions with long-lived particles detectable at colliders.

Discussed future collider prospects for probing dark matter production.

Abstract

Non-thermalized dark matter is a cosmologically valid alternative to the paradigm of weakly interacting massive particles. For dark matter belonging to a $Z_2$-odd sector that contains in addition a thermalized mediator particle, dark matter production proceeds in general via both the freeze-in and superWIMP mechanism. We highlight their interplay and emphasize the connection to long-lived particles at colliders. For the explicit example of a colored t-channel mediator model we map out the entire accessible parameter space, cornered by bounds from the LHC, big bang nucleosynthesis and Lyman-alpha forest observations, respectively. We discuss prospects for the HL- and HE-LHC.