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

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.

Note:

5 pages plus author list (18 pages total), 2 figures, 1 table, revised author list, matches published PRL version

13.85.Rm
14.65.Jk
14.80.-j
12.60.-i
p p: interaction
heavy quark: search for
family: 4
top: pair production
ATLAS
CERN LHC Coll

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