Search for W' → tb decays in the hadronic final state using pp collisions at √s=13TeV with the ATLAS detector

A search for W ^′-boson production in the W ^′→tb¯→qq¯ ^′bb¯ decay channel is presented using 36.1fb ⁻¹ of 13 TeV proton–proton collision data collected by the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The search is interpreted in terms of both a left-handed and a right-handed chiral W ^′ boson within the mass range 1–5 TeV. Identification of the hadronically decaying top quark is performed using jet substructure tagging techniques based on a shower deconstruction algorithm. No significant deviation from the Standard Model prediction is observed and the results are expressed as upper limits on the W ^′→tb¯ production cross-section times branching ratio as a function of the W ^′-boson mass. These limits exclude W ^′ bosons with right-handed couplings with masses below 3.0 TeV and W ^′ bosons with left-handed couplings with masses below 2.9 TeV, at the 95% confidence level.