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Search for CP Violation in the Decay Z -> b (b bar) g

Martin Wunsch
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Abstract

About three million hadronic decays of the Z collected by ALEPH in the years 1991-1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z -> b \bar{b} g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, ${\hat{h}}_b = {\hat{h}}_{Ab}g_{Vb}-{\hat{h}}_{Vb}g_{Ab}$ and $h^{\ast}_b = \sqrt{\hat{h}_{Vb}^{2}+\hat{h}_{Ab}^{2}}$, limits of \hat{h}_b < 0.59$ and $h^{\ast}_{b} < 3.02$ are given at 95\% CL.

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Martin Wunsch. 1996-08-01. Search for CP Violation in the Decay Z -> b (b bar) g. https://doi.org/10.1016/s0920-5632(97)00009-1

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