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arXiv · hep-ex/9908031

Symmetry Tests in Polarized Z0 Decays to bbg

SLD Collaboration·K. Abe
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Abstract

Angular asymmetries have been measured in polarized Z0 decays to bbg collected by the SLD experiment at the SLC. A high purity bbg event sample is selected by utilizing B lifetime information given by the SLD CCD pixel vertex detector and the stable micron-size SLC beams, and the b- and bbar-jets are identified using lifetime information and momentum-weighted track charge. The forward-backward asymmetry is observed in the b-quark polar angle distribution, and the parity-violation parameter is measured to test the Standard Model. Two angular correlations between the three-jet plane and the Z0 polarization are studied. The CP-even and T-odd, and the CP-odd and T-odd, angular asymmetries are sensitive to physics beyond the Standard Model. The latter requires tagging both the b- and bbar-jet. We measure the expectation values of these quantities to be consistent with zero and set limits on the correlations at the 5% level.

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SLD Collaboration, K. Abe. 1999-08-06. Symmetry Tests in Polarized Z0 Decays to bbg. https://arxiv.org/abs/hep-ex/9908031

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