Measurements of $A_{LR}$, $A_{lepton}$ and $A_{b}$ from SLD

Jorge P. Fernandez; representing the SLD Collaboration

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arXiv · hep-ex/9903040

Measurements of $A_{LR}$, $A_{lepton}$ and $A_{b}$ from SLD

Jorge P. Fernandez·representing the SLD Collaboration

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Abstract

We present the measurements of the leptonic asymmetries in $Z^0$ decays measured by the SLD experiment at SLAC. A data sample of approximately 550,000 $Z^0$ bosons are used for the preliminary measurement of $A_{LR}(A_{e})$ and the leptonic final state measurements of $A_{e}$, $A_μ$ and $A_τ$, representing the entire set of 1992-1998 SLD runs. When combining all results, a preliminary value for the effective weak mixing angle is obtained: ${\sin}^2θ_{W}^{eff} = 0.23109 \pm 0.00029$. We also present the direct measurements of $A_{b}$ from left-right forward-backward asymmetries, using partial data samples from 1993-1998 SLD runs. The preliminary value combines jet charge, cascade kaon and semileptonic decay analyses to obtain $A_{b} = 0.866 \pm 0.036$.

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Jorge P. Fernandez, representing the SLD Collaboration. 1999-03-17. Measurements of $A_{LR}$, $A_{lepton}$ and $A_{b}$ from SLD. https://arxiv.org/abs/hep-ex/9903040

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