Search for narrow H$\gamma$ resonances in proton-proton collisions at $\sqrt{s} =$ 13 TeV

TL;DR

This paper reports a search for narrow resonances decaying into a Higgs boson and a photon in proton-proton collisions at 13 TeV, setting new upper limits on such resonances in the 720-3250 GeV mass range.

Contribution

First search for Hγ resonances in proton-proton collisions at 13 TeV with CMS, providing the most stringent constraints to date.

Findings

No significant excess observed over the standard model predictions.

Upper limits set on resonance production cross sections across the 720-3250 GeV mass range.

Results improve previous constraints on heavy narrow Hγ resonances.

Abstract

A search for heavy, narrow resonances decaying to a Higgs boson and a photon (H$\gamma$) has been performed in proton-proton collision data at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$ collected with the CMS detector at the LHC in 2016. Events containing a photon and a Lorentz-boosted hadronically decaying Higgs boson that is reconstructed as a single, large-radius jet are considered, and the $\gamma$+jet invariant mass spectrum is analyzed for the presence of narrow resonances. To increase the sensitivity of the search, events are categorized depending on whether the large-radius jet can be identified as a result of the merging of two jets originating from b quarks. Results in both categories are found to agree with the predictions of the standard model. Upper limits on the production of H$\gamma$ resonances are set as a function of the resonance mass in the range of 720-3250 GeV, representing the most stringent constraints to date.