Advisor(s)
Abstract(s)
This Letter presents a search for high-mass resonances decaying into @t^+@t^- final states using proton-proton collisions at s=7 TeV produced by the Large Hadron Collider. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 4.6 fb^-^1. No statistically significant excess above the Standard Model expectation is observed 95% credibility upper limits are set on the cross section times branching fraction of Z^' resonances decaying into @t^+@t^- pairs as a function of the resonance mass. As a result, Z^' bosons of the Sequential Standard Model with masses less than 1.40 TeV are excluded at 95% credibility.