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arXiv · hep-ph/0002022

Limits on a Composite Higgs Boson

Abstract

Precision electroweak data are generally believed to constrain the Higgs boson mass to lie below approximately 190 GeV at 95% confidence level. The standard Higgs model is, however, trivial and can only be an effective field theory valid below some high energy scale characteristic of the underlying non-trivial physics. Corrections to the custodial isospin violating parameter T arising from interactions at this higher energy scale dramatically enlarge the allowed range of Higgs mass. We perform a fit to precision electroweak data and determine the region in the (m_H, Delta T) plane that is consistent with experimental results. Overlaying the estimated size of corrections to T arising from the underlying dynamics, we find that a Higgs mass up to 500 GeV is allowed. We review two composite Higgs models which can realize the possibility of a phenomenologically acceptable heavy Higgs boson. We comment on the potential of improvements in the measurements of m_t and M_W to improve constraints on composite Higgs models.

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BibTeXRIS

R. Sekhar Chivukula, Nick Evans, Christian Hoelbling. 2000-06-06. Limits on a Composite Higgs Boson. https://doi.org/10.1103/physrevlett.85.511

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