Dynamical Dark Matter, MATHUSLA, and the Lifetime Frontier

TL;DR

This paper explores how the proposed MATHUSLA detector at CERN can detect long-lived particles from dark matter models, especially the Dynamical Dark Matter framework, potentially confirming unique theoretical predictions.

Contribution

It analyzes MATHUSLA's capability to probe the parameter space of Dynamical Dark Matter, highlighting its potential to confirm aspects of the model difficult to test otherwise.

Findings

MATHUSLA can detect LLPs with lifetimes up to 10^7 meters.

It can probe broad mass and lifetime ranges of dark states.

Potential to confirm unique features of the DDM framework.

Abstract

MATHUSLA is a proposed surface detector at CERN that would be able to observe the decays of non-hadronic electrically neutral long-lived particles (LLPs) with almost no background or trigger limitations. This would allow MATHUSLA to probe sub-GeV to TeV masses and lifetimes up to $c\tau \sim 10^7~{\rm m}$. MATHUSLA can play an important role in probing dark-matter scenarios involving extended hidden sectors, where additional dark states often manifest as LLPs. A prime example of such a scenario is furnished by the Dynamical Dark Matter (DDM) framework, which intrinsically gives rise to large ensembles of dark states exhibiting a broad range of masses and lifetimes. In this paper, we examine the extent to which MATHUSLA can probe the DDM parameter space, and we demonstrate that MATHUSLA may be capable of providing direct confirmation of certain unique aspects of the DDM framework which might be difficult to probe in other ways.