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arXiv · 0906.1172

Direct measurement of the mass difference between top and antitop quarks

D0 Collaboration·V. Abazov
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Abstract

We present a measurement of the mass difference between t and tbar quarks observed in lepton+jets final states of ttbar events in 1 fb-1 of data collected with the D0 detector at the Fermilab Tevatron Collider in ppbar collisions at sqrt(s)=1.96 TeV. The observed mass difference of 3.8+-3.7 GeV is consistent with the equality of t and tbar masses. This is the first direct measurement of a mass difference between a quark and its antiquark partner.

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D0 Collaboration, V. Abazov. 2009-09-26. Direct measurement of the mass difference between top and antitop quarks. https://doi.org/10.1103/physrevlett.103.132001

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