The result of a direct search for the exotic Higgs boson decay $\mathrm{H}\rightarrow\mathcal{A}\mathcal{A}$, $\mathcal{A}\rightarrow\gamma\gamma$ is presented, using events with a final state containing two photons. The hypothetical particle $\mathcal{A}$ is a low-mass, boosted scalar decaying promptly to two highly merged photons, misreconstructed as a single photon-like object. The data were collected by the CMS experiment at the CERN LHC from proton-proton collisions at \sqrt{s} = 13~\mathrm{TeV}, corresponding to an integrated luminosity of 136~\mathrm{fb}^{-1}. No excess of events above the estimated background is found. Upper limits on the branching fraction $\mathcal{B}(\mathrm{H} \rightarrow \mathcal{A}\mathcal{A} \rightarrow 4\gamma)$ of 0.9--3.3 $\times10^{-3}$ are set at the $95\%$ confidence level for masses of $\mathcal{A}$ in the range 0.1 < m_{\mathcal{A}} < 1.2~\mathrm{GeV}.

Log in to your administrator account to edit.