Dark matter and Higgs boson collider implications of fermions in an abelian-gauged hidden sector

TL;DR

This paper explores how adding fermions to an abelian-gauged hidden sector can produce viable dark matter candidates and significantly alter Higgs boson signatures at the LHC, including potential invisible decays.

Contribution

It demonstrates that fermions in a hidden sector can serve as dark matter and modify Higgs phenomenology, with implications for collider and dark matter detection.

Findings

Lightest fermion can be dark matter with correct relic abundance.

Fermions can induce large invisible Higgs decay widths.

Invisible Higgs decays detectable at the LHC via vector boson fusion.

Abstract

We add fermions to an abelian-gauged hidden sector. We show that the lightest can be the dark matter with the right thermal relic abundance, and discovery is within reach of upcoming dark matter detectors. We also show that these fermions change Higgs boson phenomenology at the Large Hadron Collider (LHC), and in particular could induce a large invisible width to the lightest Higgs boson state. Such an invisibly decaying Higgs boson can be discovered with good significance in the vector boson fusion channel at the LHC.