Search for a new spin-1 boson using ATLAS detector data

We present the search for signatures of dark matter where the Standard Model Higgs boson decays to a four lepton final state via the decay of two vector bosons through the channel H -> ZdZd -> 4l. In this case, Zd is the dark vector boson and 4l contains electrons and muons which can be 2e2μ, 4e or 4μ. The mass range under consideration for Zd lies between 15 - 60 GeV. Proton-proton collision data from the ATLAS detector was used to conduct this search corresponding to an integrated luminosity of 139 fb-1 and a center of mass energy of √s = 13 TeV. No significant excesses were observed. In light of the lack of excesses, 95% CL limits were set on the branching ratio and the mass of the dark vector boson and the mixing parameter κ which is related to the Hidden Abelian Higgs Model used in the search. Improvements on the limits from the previous iteration of the analysis are observed.