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arXiv · 1106.2063

Direct measurement of the mass difference between top and antitop quarks

D0 Collaboration
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Abstract

We present a direct measurement of the mass difference between top and antitop quarks (dm) in lepton+jets top-antitop final states using the "matrix element" method. The purity of the lepton+jets sample is enhanced for top-antitop events by identifying at least one of the jet as originating from a b quark. The analyzed data correspond to 3.6 fb-1 of proton-antiproton collisions at 1.96 TeV acquired by D0 in Run II of the Fermilab Tevatron Collider. The combination of the e+jets and mu+jets channels yields dm = 0.8 +/- 1.8 (stat) +/- 0.5 (syst) GeV, which is in agreement with the standard model expectation of no mass difference.

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D0 Collaboration. 2011-08-12. Direct measurement of the mass difference between top and antitop quarks. https://doi.org/10.1103/physrevd.84.052005

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