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arXiv · hep-ex/9611021

Search for a Fourth Generation Charge -1/3 Quark via Flavor Changing Neutral Current Decay

D0 Collaboration
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Abstract

We report on a search for pair production of a fourth generation charge -1/3 quark (b') in pbar p collisions at sqrt(s) = 1.8 TeV at the Fermilab Tevatron using an integrated luminosity of 93 pb^-1. Both quarks are assumed to decay via flavor changing neutral currents (FCNC). The search uses the signatures gamma + 3 jets + mu-tag and 2 gamma + 2 jets. We see no significant excess of events over the expected background. We place an upper limit on the production cross section times branching fraction that is well below theoretical expectations for a b' quark decaying exclusively via FCNC for b' quark masses up to m(Z) + m(b).

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D0 Collaboration. 1996-11-26. Search for a Fourth Generation Charge -1/3 Quark via Flavor Changing Neutral Current Decay. https://doi.org/10.1103/physrevlett.78.3818

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