Multi-component Dark Matter through a Radiative Higgs Portal

TL;DR

This paper investigates a multi-component dark matter model with Higgs portal interactions, involving vector-like fermions and gauge groups, analyzing relic abundance and experimental constraints.

Contribution

It introduces a novel multi-component dark matter model with both fermionic and vector boson candidates connected via a radiative Higgs portal.

Findings

Model is highly constrained when fermionic dark matter dominates.

Relic abundance is significantly affected by Higgs interactions.

Experimental constraints from Higgs invisible width and direct detection are critical.

Abstract

We study a multi-component dark matter model where interactions with the Standard Model are primarily via the Higgs boson. The model contains vector-like fermions charged under $SU(2)_W \times U(1)_Y$ and under the dark gauge group, $U(1)^\prime$. This results in two dark matter candidates. A spin-1 and a spin-1/2 candidate, which have loop and tree-level couplings to the Higgs, respectively. We explore the resulting effect on the dark matter relic abundance, while also evaluating constraints on the Higgs invisible width and from direct detection experiments. Generally, we find that this model is highly constrained when the fermionic candidate is the predominant fraction of the dark matter relic abundance.