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Direct Measurement of the Top Quark Charge at Hadron Colliders

U. Baur·M. Buice·L. H. Orr
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Abstract

We consider photon radiation in tbar-t events at the upgraded Fermilab Tevatron and the CERN Large Hadron Collider (LHC) as a tool to measure the electric charge of the top quark. We analyze the contributions of tbar-t-gamma production and radiative top quark decays to p-p, pbar-p -> gamma l^+/- nu bbar-b jj, assuming that both b-quarks are tagged. With 20~fb^{-1} at the Tevatron, the possibility that the ``top quark'' discovered in Run I is actually an exotic charge -4/3 quark can be ruled out at the 95% confidence level. At the LHC, it will be possible to determine the charge of the top quark with an accuracy of about 10%.

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U. Baur, M. Buice, L. H. Orr. 2001-06-28. Direct Measurement of the Top Quark Charge at Hadron Colliders. https://doi.org/10.1103/physrevd.64.094019

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