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arXiv · hep-ph/0308198

CP Violation in the 3 Jet and 4 Jet Decays of the Z Boson at GigaZ

O. Nachtmann·C. Schwanenberger
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Abstract

We review CP-violating effects in Z --> 3 jet and Z --> 4 jet decays, assuming the presence of CP-violating effective Z b bbar G and Z b bbar G G couplings. Longitudinal beam polarization is included in the studies. We propose a direct search for such CP-violating couplings by using various CP-odd observables. The data of a future linear collider running at the Z-resonance in the so-called GigaZ option should give significant information on the couplings. Finally we show that stringent bounds on the mass of excited b quarks can be derived if appropriate couplings are of a size characteristic of a strong interaction.

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O. Nachtmann, C. Schwanenberger. 2003-11-09. CP Violation in the 3 Jet and 4 Jet Decays of the Z Boson at GigaZ. https://doi.org/10.1140/epjc%2Fs2003-01369-y

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