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arXiv · hep-ph/9511364

Possible explanation of Zbb vertex anomaly in one-family technicolor models

N. Kitazawa·T. Yanagida
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Abstract

In technicolor theories a large radiative correction to the Zbb vertex generally emerges, because of the large top quark mass and SU(2)_L gauge symmetry. The correction can give us an explanation for the deviation of the experimental value of R_b from the standard model prediction. However, generally the T parameter becomes unacceptably large. We show that in the one-family technicolor model recently proposed by the authors all the S, T, and U parameters can be consistent with the experimental bounds while the observed anomaly of R_b is naturally explained.

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N. Kitazawa, T. Yanagida. 1995-11-17. Possible explanation of Zbb vertex anomaly in one-family technicolor models. https://doi.org/10.1103/physrevd.54.3594

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