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Updated: May 11, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Viability of strongly coupled scenarios with a light Higgs-like boson
Antonio Pich1, Ignasi Rosell, Juan José Sanz-Cillero
1Departament de Física Teòrica, IFIC, Universitat de València-CSIC, Apartat de Correus 22085, 46071 València, Spain.
Abstract:
We present a one-loop calculation of the oblique S and T parameters within strongly coupled models of electroweak symmetry breaking with a light Higgs-like boson. We use a general effective Lagrangian, implementing the chiral symmetry breaking SU(2)(L) [Symbol: see text]SU(2)(R) → SU(2)(L+R) with Goldstone bosons, gauge bosons, the Higgs-like scalar, and one multiplet of vector and axial-vector massive resonance states. Using a dispersive representation and imposing a proper ultraviolet behavior, we obtain S and T at the next-to-leading order in terms of a few resonance parameters. The experimentally allowed range forces the vector and axial-vector states to be heavy, with masses above the TeV scale, and suggests that the Higgs-like scalar should have a WW coupling close to the standard model one. Our conclusions are generic and apply to more specific scenarios such as the minimal SO(5)/SO(4) composite Higgs model.
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