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

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 $A_{b} = 0.866 \pm 0.036$.