Search for heavy resonances decaying to a photon and a hadronically decaying $Z/W/H$ boson in $pp$ collisions at $\sqrt{s}=13$ $\mathrm{TeV}$ with the ATLAS detector

TL;DR

This paper reports a search for new heavy resonances decaying into a photon and a hadronically decaying Z, W, or Higgs boson in proton-proton collisions at 13 TeV, setting upper limits on their production cross sections.

Contribution

First search to set limits on resonances decaying to H+γ in the 1.0 to 3.0 TeV mass range using ATLAS data at 13 TeV.

Findings

No significant excess observed over Standard Model predictions.

Upper limits established on production cross sections for various resonance masses.

First limits on H+γ resonance decays in this mass range.

Abstract

Many extensions of the Standard Model predict new resonances decaying to a $Z$, $W$, or Higgs boson and a photon. This paper presents a search for such resonances produced in $pp$ collisions at $\sqrt{s} = 13$ $\mathrm{TeV}$ using a dataset with an integrated luminosity of 36.1 fb$^{-1}$ collected by the ATLAS detector at the Large Hadron Collider. The $Z/W/H$ bosons are identified through their decays to hadrons. The data are found to be consistent with the Standard Model expectation in the entire investigated mass range. Upper limits are set on the production cross section times branching fraction for resonance decays to $Z/W+\gamma$ in the mass range from 1.0 to 6.8 $\mathrm{TeV}$, and for the first time into $H+\gamma$ in the mass range from 1.0 to 3.0 $\mathrm{TeV}$.