Gravitational wave effects and phenomenology of a two-component dark matter model

TL;DR

This paper explores a scale-invariant extension of the Standard Model with two dark matter candidates, analyzing its parameter space, phase transition properties, and potential gravitational wave signals detectable by future observatories.

Contribution

It introduces a two-component dark matter model with a new U(1) gauge symmetry, examining its phenomenology, phase transition, and gravitational wave signatures within experimental constraints.

Findings

Multiple parameter points satisfy phenomenological bounds.

The model allows for a first order electroweak phase transition.

Predicted gravitational waves could be detected by LISA and BBO.

Abstract

We study an extension of the Standard Model (SM) which could have two candidates for dark matter (DM) including a Dirac fermion and a vector dark matter (VDM) under a new $U(1)$ gauge group in the hidden sector. The model is classically scale-invariant and the electroweak symmetry breaks because of loop effects. We investigate the parameter space allowed by current experimental constraints and phenomenological bounds. We probe the parameter space of the model in the mass range $1< M_V<5000$ GeV and $1<M_{\psi}<5000$ GeV. It has been shown that there are many points in this mass range that are in agreement with all phenomenological constraints. The electroweak phase transition has been discussed and it has been shown that there is region in the parameter space of the model consistent with DM relic density and direct detection constraints that, at the same time, can lead to first order electroweak phase transition. The gravitational waves produced during the phase transition could be probed by future space-based interferometers such as LISA and BBO.