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arXiv · 1202.6540

Search for down-type fourth generation quarks with the ATLAS detector in events with one lepton and hadronically decaying W bosons

ATLAS Collaboration
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Abstract

This Letter presents a search for pair production of heavy down-type quarks decaying via b'->Wt in the lepton + jets channel, as b'b'->WtWt->bbWWWW->lvbbqqqqqq. In addition to requiring exactly one lepton, large missing transverse momentum and at least six jets, the invariant mass of nearby jet pairs is used to identify high transverse momentum W bosons. In data corresponding to an integrated luminosity of 1.04 fb^-1 from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector, a heavy down-type quark with mass less than 480 GeV is excluded at the 95% confidence level.

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ATLAS Collaboration. 2012-02-29. Search for down-type fourth generation quarks with the ATLAS detector in events with one lepton and hadronically decaying W bosons. https://doi.org/10.1103/physrevlett.109.032001

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