Search for heavy resonances in the $\ell\ell qq$ final state in pp collisions at $\sqrt s =13$ TeV with ATLAS

A search for heavy resonances decaying to a pair of $Z$ bosons is performed using proton-proton collision data produced at $\sqrt{s}=13$ TeV and recorded by the ATLAS detector at the LHC. The data correspond to an integrated luminosity of 3.2 fb$^{-1}$. Diboson resonant production is expected in several Standard Model extension scenarios. The $ZZ$ decay mode considered corresponds to one $Z$ boson decaying to a pair of charged leptons and the other decaying to a pair of quarks. No evidence for the production of resonances decaying to a $ZZ$ pair is observed. Upper bounds on the production cross sections at $\sqrt{s}=13$ TeV times their decay branching ratios to $ZZ$ pairs are derived for a heavy Higgs boson and a spin-2 Randall-Sundrum graviton scenario.