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arXiv · hep-ph/9504332

Extended technicolor contribution to the Zbb vertex

Kaoru Hagiwara·Noriaki Kitazawa
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Abstract

We show that the flavor-diagonal gauge boson of the extended technicolor theory contributes with opposite sign to the standard model correction for the $Zbb$ vertex. This mechanism can naturally explain the deviation of the LEP result from the standard model prediction for the partial width $Γ(Z \rightarrow b{\bar b})$. A smaller value of the QCD coupling, $α_s(m_Z) \simeq 0.115$, is then preferred by the $Γ(Z \rightarrow \mbox{hadron})$ data, which is consistent with both the recent Lattice-QCD estimate and the Particle Data Group average.

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Kaoru Hagiwara, Noriaki Kitazawa. 1995-04-19. Extended technicolor contribution to the Zbb vertex. https://doi.org/10.1103/physrevd.52.5374

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