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arXiv · 1211.5543

The S parameter for a Light Composite Higgs: a Dispersion Relation Approach

Axel Orgogozo·Slava Rychkov
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Abstract

We derive a dispersion relation for the S parameter in the SO(5)/SO(4) Minimal Composite Higgs model. This generalizes the Peskin-Takeuchi formula to the case when a light Higgs boson is present in the spectrum. Our result combines an IR effect due to the reduction in the Higgs boson couplings with a UV contribution from the strong sector. It also includes a finite matching term, achieving a very good relative accuracy O(m_h/m_\rho). We apply our formula in several toy examples, modeling the UV spectral density via Vector Meson Dominance.

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Axel Orgogozo, Slava Rychkov. 2012-11-23. The S parameter for a Light Composite Higgs: a Dispersion Relation Approach. https://doi.org/10.1007/jhep06(2013)014

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