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New Measurement of Ab at the Z Resonance using a Vertex-Charge Technique

The SLD Collaboration·K. Abe
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Abstract

We present a new preliminary measurement of the parity-violation parameter Ab using a self-calibrating vertex-charge technique. In the SLD experiment we observe hadronic decays of polarized Z bosons produced in collisions between longitudinally polarized electrons and unpolarized positrons at the SLAC Linear Collider. A sample of bb events is selected using the topologically reconstructed mass of B hadrons. From out 1996-8 data sample of approximately 400,000 hadronic Z decays, we obtain Ab = 0.897 +/- 0.027 (stat) +0.036/-0.034 (syst).

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The SLD Collaboration, K. Abe. 1999-07-27. New Measurement of Ab at the Z Resonance using a Vertex-Charge Technique. https://arxiv.org/abs/hep-ex/9907050

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