Vector dark matter and LHC constraints, including a 95 GeV light Higgs boson

TL;DR

This paper investigates how LHC data constrains a vector dark matter model with a light Higgs boson around 95 GeV, excluding certain parameter regions and complementing relic density and direct detection limits.

Contribution

It provides the first comprehensive LHC-based constraints on a vector dark matter model with a light Higgs boson, including new limits for a 95 GeV Higgs.

Findings

LHC results exclude all scalar Higgs portal masses for the light VDM.

Certain parameter space regions are ruled out by ATLAS and CMS data.

New limits are set for a 95 GeV light Higgs boson in the model.

Abstract

We study LHC searches for an extension of the Standard Model (SM) by exploiting an additional Abelian $U_D(1)$ gauge symmetry and a complex scalar Higgs portal. As the scalar is charged under this gauge symmetry, a vector dark matter (VDM) candidate can satisfy the observed relic abundance and limits from direct dark matter (DM) searches. The ATLAS and CMS experiments have developed a broad search program for the DM candidates, including associate production of Higgs boson, $Z$ boson, and top quark that couple to DM. In this paper, we perform an extensive analysis to constrain the model by using these experiments at LHC. It can be seen that the LHC results can exclude some parts of the parameter space that are still allowed by relic density and the direct detection searches. Using the LHC results, all scalar Higgs portal masses are excluded for the light VDM. Furthermore, exclusion limits on the parameter space of the model by using the new results of the CMS and ATLAS Collaborations for a new light Higgs boson with mass $\sim95~\rm GeV$ are provided.