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arXiv · hep-ex/0009019

WW Production Cross Section and W Branching Fractions in e+e- Collisions at 189 GeV

The OPAL collaboration·G. Abbiendi
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Abstract

From a data sample of 183 pb^-1 recorded at a center-of-mass energy of roots = 189 GeV with the OPAL detector at LEP, 3068 W-pair candidate events are selected. Assuming Standard Model W boson decay branching fractions, the W-pair production cross section is measured to be sigmaWW = 16.30 +- 0.34(stat.) +- 0.18(syst.) pb. When combined with previous OPAL measurements, the W boson branching fraction to hadrons is determined to be 68.32 +- 0.61(stat.) +- 0.28(syst.) % assuming lepton universality. These results are consistent with Standard Model expectations.

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The OPAL collaboration, G. Abbiendi. 2000-09-07. WW Production Cross Section and W Branching Fractions in e+e- Collisions at 189 GeV. https://doi.org/10.1016/s0370-2693(00)01085-6

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