Search for high-mass $\mathrm{Z}\gamma$ resonances in proton-proton collisions at $\sqrt{s}= 13~\mathrm{TeV}$

A search for high-mass resonances decaying to a Z boson and a photon is presented. The analysis is based on a data set of proton-proton collisions at a center-of-mass energy of $13~\mathrm{TeV}$ , corresponding to an integrated luminosity of $35.9~\mathrm{fb}^{-1}$ collected with the CMS detector at the LHC in 2016. In the leptonic channel the Z boson candidates are reconstructed using an electron or a muon pair. In the hadronic channel they are identified using a large-radius jet containing either light-quark or b quark decay products of the Z boson, identified using jet substructure and advanced b tagging techniques. The results in the leptonic and hadronic channels are combined and interpreted in terms of upper limits on the production cross section of narrow and broad spin-0 resonances with masses between 0.3 and $4.0~\mathrm{TeV}$. These limits are most stringent to date for a wide range of resonance masses.