Pursuit of paired dijet resonances in the Run 2 dataset with ATLAS

New particles with large masses that decay into hadronically interactingparticles are predicted by many models of physics beyond the Standard Model. Asearch for a massive resonance that decays into pairs of dijet resonances isperformed using 140 fb$^{-1}$ of proton$-$proton collisions at $\sqrt{s}=13$TeV recorded by the ATLAS detector during Run 2 of the Large Hadron Collider.Resonances are searched for in the invariant mass of the tetrajet system, andin the average invariant mass of the pair of dijet systems. A data-drivenbackground estimate is obtained by fitting the tetrajet and dijet invariantmass distributions with a four-parameter dijet function and a search for localexcesses from resonant production of dijet pairs is performed. No significantexcess of events beyond the Standard Model expectation is observed, and upperlimits are set on the production cross-sections of new physics scenarios.