Search for high-mass $W\gamma$ and $Z\gamma$ resonances in the hadronic final state using 139 fb$^{-1}$ of pp collisions at $\sqrt{s}$= 13 TeV with the ATLAS Detector

A search for high-mass charged and neutral bosons decaying to $W\gamma$ and $Z\gamma$ final states is presented in this note. The analyses uses a data sample of $\sqrt{s}$ = 13 TeV proton-proton collisions with an integrated luminosity of 139 fb$^{-1}$ collected by the ATLAS detector during LHC Run 2 operation. The sensitivity of the search is determined using models of the production and decay of spin-1 charged bosons and spin-0/2 neutral bosons. The range in resonance masses explored extends from 1.0 TeV to 6.8 TeV. At such high resonance masses, it is beneficial to target the hadronic decays of the $W$ or $Z$ boson and the analysis boson tagging to improve the sensitivity. No evidence for signals above the expected Standard Model backgrounds is observed, and cross-section upper limits are derived and presented for various boson production models.