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arXiv · 1106.6308

Measurement of the anomalous like-sign dimuon charge asymmetry with 9 fb^-1 of p pbar collisions

D0 Collaboration·V. Abazov
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Abstract

We present an updated measurement of the anomalous like-sign dimuon charge asymmetry Aslb for semi-leptonic $b$-hadron decays in 9.0 fb^-1 of p pbar collisions recorded with the D0 detector at a center-of-mass energy of sqrt{s} = 1.96 TeV at the Fermilab Tevatron collider. We obtain Aslb = (-0.787 +- 0.172(stat) +- 0.093 (syst))%. This result differs by 3.9 standard deviations from the prediction of the standard model and provides evidence for anomalously large CP violation in semi-leptonic neutral B decay. The dependence of the asymmetry on the muon impact parameter is consistent with the hypothesis that it originates from semi-leptonic b-hadron decays.

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D0 Collaboration, V. Abazov. 2011-06-30. Measurement of the anomalous like-sign dimuon charge asymmetry with 9 fb^-1 of p pbar collisions. https://doi.org/10.1103/physrevd.84.052007

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