Combination of searches for Higgs boson decays into a photon and a massless dark photon using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

Abstract

A combination of searches for Higgs boson decaying into a visible photon and a massless dark photon ($H\to \gamma {\gamma }_{\text{d}}$) is presented using 139 fb${}^{-1}$ of proton--proton collision data at a centre-of-mass energy of $\sqrt{s}=13$ TeV recorded by the ATLAS detector at the Large Hadron Collider. The observed (expected) 95\% confidence level upper limit on the Standard Model Higgs boson decay branching ratio is determined to be $\mathcal{B}(H\to \gamma {\gamma }_{\text{d}})<$ 1.3% (1.5)%. The search is also sensitive to higher-mass Higgs bosons decaying into the same final state. The observed (expected) 95% CL limit on the cross section times branching ratio ranges from 16 fb (26 fb) for $m_H=400$ GeV to 1.0 fb (1.5 fb) for $m_H=3$ TeV. Results are also interpreted in the context of a minimal simplified model.

35 pages in total, author list starting page 18, 4 figures, 1 tables, published on JHEP. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2023-01

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Cited by in corpus (1)

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