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arXiv · hep-ex/0010015

An improved direct measurement of leptonic coupling asymmetries with polarized Z bosons

The SLD Collaboration·K. Abe
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Abstract

We present final measurements of the Z boson-lepton coupling asymmetry parameters Ae, Amu, and Atau with the complete sample of polarized Z bosons collected by the SLD detector at the SLAC Linear Collider. From the left-right production and decay polar angle asymmetries in leptonic Z decays we measure Ae = 0.1544 +- 0.0060, Amu = 0.142 +- 0.015, and Atau = 0.136 +- 0.015. Combined with our left-right asymmetry measured from hadronic decays, we find Ae = 0.1516 +- 0.0021. Assuming lepton universality, we obtain a combined effective weak mixing angle of sin**2 theta^{eff}_W = 0.23098 +- 0.00026.

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The SLD Collaboration, K. Abe. 2000-10-06. An improved direct measurement of leptonic coupling asymmetries with polarized Z bosons. https://doi.org/10.1103/physrevlett.86.1162

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