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arXiv · hep-ph/9206225

Walking Technicolor and Electroweak Radiative Corrections

Raman Sundrum·Stephen D. H. Hsu
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Abstract

We examine the effect of walking technicolor dynamics on the electroweak $S$ parameter and contrast it with the effect of QCD-like technicolor dynamics. Our main tools are the operator product expansion for the high-momentum behavior of the electroweak gauge boson vacuum polarizations and the analyticity of these polarizations which relate their low and high momentum behaviors. We show that whereas in large QCD-like technicolor models $S$ is large and positive, in walking technicolor models a negative contribution is emphasized, related to the large anomalous dimension of the technifermion condensate. Thus in walking technicolor $S$ is determined by a large cancellation of two competing effects. This may result in much smaller values of $S$ than in QCD-like technicolor, although considerable uncertainties are involved. We conclude that it is impossible to rule out walking technicolor based on the present experimental limits on $S$ and the present theoretical technology.

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Raman Sundrum, Stephen D. H. Hsu. 1992-06-17. Walking Technicolor and Electroweak Radiative Corrections. https://doi.org/10.1016/0550-3213(93)90144-e

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