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arXiv · hep-ph/0610094

The Effects on $S$, $T$, and $U$ from Higher-Dimensional Fermion Representations

Hong-Hao Zhang·Yue Cao·Qing Wang
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Abstract

Inspired by a new class of walking technicolor models recently proposed using higher-dimensional technifermions, we consider the oblique corrections from heavy non-degenerate fermions with two classes of higher-dimensional representations of the electroweak gauge group itself. One is chiral SM-like, and the other is vector-like. In both cases, we obtain explicit expressions for $S$, $T$, $U$ in terms of the fermion masses. We find that to keep the $T$ parameter ultraviolet-finite there must be a stringent constraint on the mass non-degeneracy of a heavy fermion multiplet.

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Hong-Hao Zhang, Yue Cao, Qing Wang. 2006-10-09. The Effects on $S$, $T$, and $U$ from Higher-Dimensional Fermion Representations. https://doi.org/10.1142/s0217732307022736

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