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arXiv · hep-ph/9510334

Extended technicolor contribution to the Zbb vertex

N. Kitazawa
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Abstract

The deviation of the experimental value of $R_b \equiv Γ_b/Γ_h$ from the standard-model prediction can be naturally explained in the extended technicolor scenario.The diagonal extended technicolor gauge boson which flavor-diagonally couples with both the ordinary fermions and the techni-fermions plays an important role in order to have the appropriate radiative correction to the $Zbb$ vertex. But since the diagonal extended technicolor gauge boson gives too large positive contribution to the $T$ parameter, we need some new mechanisms which generate negative contribution to the $T$ parameter.

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N. Kitazawa. 1995-10-18. Extended technicolor contribution to the Zbb vertex. https://doi.org/10.1143/ptps.123.97

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