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arXiv · 1103.1871

Measurement of spin correlation in ttbar production using dilepton final states

D0 Collaboration·V. Abazov et al.
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Abstract

We measure the correlation between the spin of the top quark and the spin of the anti-top quark in (ttbar -> W+ W- b bbar -> l+ nu b l- nubar bbar) final states produced in ppbar collisions at a center of mass energy sqrt(s)=1.96 TeV, where l is an electron or muon. The data correspond to an integrated luminosity of 5.4 fb-1 and were collected with the D0 detector at the Fermilab Tevatron collider. The correlation is extracted from the angles of the two leptons in the t and tbar rest frames, yielding a correlation strength C= 0.10^{+0.45}_{-0.45}, in agreement with the NLO QCD prediction within two standard deviations, but also in agreement with the no correlation hypothesis.

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D0 Collaboration, V. Abazov et al.. 2011-03-09. Measurement of spin correlation in ttbar production using dilepton final states. https://doi.org/10.1016/j.physletb.2011.05.077

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