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arXiv · hep-ex/0002024

Measurements of R_b, A_FB^b and A_FB^c in e+e- Collisions at 130-189 GeV

The OPAL collaboration·G. Abbiendi
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Abstract

The cross-section ratio Rb=sigma(e+e- to b-antib)/sigma(e+e- to q-antiq) and the bottom and charm forward-backward asymmetries AFB^b and AFB^c are measured using event samples collected by the OPAL detector at centre-of-mass energies between 130 and 189 GeV. Events with bottom quark production are selected with a secondary vertex tag, and a hemisphere charge algorithm is used to extract AFB^b. In addition, the bottom and charm asymmetries are measured using leptons from semileptonic decays of heavy hadrons and pions from D*+ to D0pi+ decays. The results are in agreement with the Standard Model predictions.

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The OPAL collaboration, G. Abbiendi. 2000-02-08. Measurements of R_b, A_FB^b and A_FB^c in e+e- Collisions at 130-189 GeV. https://doi.org/10.1007/s100520050002

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