Categorisation and Detection of Dark Matter Candidates from String/M-theory Hidden Sectors

TL;DR

This paper investigates dark matter candidates from string/M-theory hidden sectors, identifying viable fermionic candidates and gauge boson mediators, and assesses their detectability through experiments and collider searches.

Contribution

It categorizes dark matter candidates from string/M-theory considering top-down constraints and supersymmetry breaking mechanisms, highlighting the viability of fermionic dark matter with gauge boson mediators.

Findings

Weakly-coupled hidden sectors favor fermionic dark matter.

Most relic density mechanisms imply a gauge boson mediator like a dark Z'.

Current and future experiments can constrain or discover these candidates.

Abstract

We study well-motivated dark matter candidates arising from weakly-coupled hidden sectors in compactified string/$M$-theory. Imposing generic top-down constraints greatly restricts allowed candidates. By considering the possible mechanisms for achieving the correct dark matter relic density, we compile categories of viable dark matter candidates and annihilation mediators. We consider the case where supersymmetry breaking occurs via moduli stabilisation and is gravitationally mediated to the visible and other hidden sectors, without assuming sequestering of the sector in which supersymmetry is broken. We find that in this case, weakly-coupled hidden sectors only allow for fermionic dark matter. Additionally, most of the mechanisms for obtaining the full relic density only allow for a gauge boson mediator, such as a dark $Z'$. Given these considerations, we study the potential for discovering or constraining the allowed parameter space given current and future direct detection experiments, and direct production at the LHC. We also present a model of a hidden sector which would contain a satisfactory dark matter candidate.