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Electroweak Precision Measurements with Leptons

James E. Brau
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Abstract

The precision measurements of lepton electroweak parameters at SLD and LEP are reviewed and discussed. The updated SLD weak mixing angle measurement from $A_{LR}$ and the lepton left-right forward-backward asymmetries is $\sin^2θ_W^{eff} = 0.23099 \pm 0.00026$, and the combined SLD/LEP lepton-based value is $0.23119 \pm 0.00020$. This value differs by over $3σ$ from the comparable quark-based value.

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James E. Brau. 1999-11-26. Electroweak Precision Measurements with Leptons. https://arxiv.org/abs/hep-ex/9911040

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