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arXiv · hep-ex/0312043

Measurement of the partial widths of the Z into up- and down-type quarks

The OPAL collaboration·G. Abbiendi
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Abstract

Using the entire OPAL LEP1 on-peak Z hadronic decay sample, Z -> qbarq gamma decays were selected by tagging hadronic final states with isolated photon candidates in the electromagnetic calorimeter. Combining the measured rates of Z -> qbarq gamma decays with the total rate of hadronic Z decays permits the simultaneous determination of the widths of the Z into up- and down-type quarks. The values obtained, with total errors, were Gamma u = 300 ^{+19}_{-18} MeV and Gamma d = 381 ^{+12}_{-12} MeV. The results are in good agreement with the Standard Model expectation.

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The OPAL collaboration, G. Abbiendi. 2003-12-15. Measurement of the partial widths of the Z into up- and down-type quarks. https://doi.org/10.1016/j.physletb.2004.02.046

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