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arXiv · 1504.02750

One-loop effects from spin-1 resonances in Composite Higgs models

Roberto Contino·Matteo Salvarezza
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Abstract

We compute the 1-loop correction to the electroweak observables from spin-1 resonances in SO(5)/SO(4) composite Higgs models. The strong dynamics is modeled with an effective description comprising the Nambu-Goldstone bosons and the lowest-lying spin-1 resonances. A classification is performed of the relevant operators including custodially-breaking effects from the gauging of hypercharge. The 1-loop contribution of the resonances is extracted in a diagrammatic approach by matching to the low-energy theory of Nambu-Goldstone bosons. We find that the correction is numerically important in a significant fraction of the parameter space and tends to weaken the bounds providing a negative shift to the S parameter.

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Roberto Contino, Matteo Salvarezza. 2015-04-10. One-loop effects from spin-1 resonances in Composite Higgs models. https://arxiv.org/abs/1504.02750

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