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

ATLAS Collaboration

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 collisi…