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Improved Direct Measurement of the Parity-Violation Parameter A_b Using a Mass Tag and Momentum-Weighted Track Charge

SLD Collaboration·Kenji Abe
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Abstract

We present an improved direct measurement of the parity-violation parameter A_b in the Z boson-b quark coupling using a self-calibrating track-charge technique applied to a sample enriched in Z -> b b-bar events via the topological reconstruction of the B hadron mass. Manipulation of the SLC electron-beam polarization permits the measurement of A_b to be made independently of other Z-pole coupling parameters. From the 1996-98 sample of 400,000 hadronic Z decays, produced with an average beam polarization of 73.4%, we find A_b = 0.906 +/- 0.022(stat.) +/- 0.023(syst.).

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SLD Collaboration, Kenji Abe. 2003-02-10. Improved Direct Measurement of the Parity-Violation Parameter A_b Using a Mass Tag and Momentum-Weighted Track Charge. https://doi.org/10.1103/physrevlett.90.141804

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