Search for pair production of a heavy up-type quark decaying to a W boson and a b quark in the lepton+jets channel with the ATLAS detector

TL;DR

This paper reports a search for a hypothetical heavy up-type quark decaying into a W boson and a b quark, using ATLAS detector data, finding no evidence and setting a mass limit above 404 GeV.

Contribution

First search for pair production of a heavy up-type quark decaying to W and b in the lepton+jets channel with ATLAS data.

Findings

No significant excess observed above background.

Lower mass limit for t' set at 404 GeV at 95% confidence level.

Analysis based on 1.04 fb^-1 of 7 TeV proton-proton collisions.

Abstract

A search is presented for production of a heavy up-type quark (t') together with its antiparticle, assuming subsequent decay to a W boson and a b quark, t't'bar -> W+b W-bbar. The search is based on 1.04 fb^-1 of proton-proton collisions at sqrt(s) = 7 TeV collected by the ATLAS detector at the CERN Large Hadron Collider. Data are analyzed in the lepton+jets final state, characterized by a high transverse momentum isolated electron or muon, high missing transverse momentum and at least three jets. No significant excess of events above the background expectation is observed. A 95% C.L. lower limit is set at m(t') > 404 GeV.