CERN Accelerating science

Article
Report number	arXiv:1511.00592 ; CERN-PH-TH-2015-280 ; CERN-PH-TH-2015-280
Title	Dispersion Relations for Electroweak Observables in Composite Higgs Models
Author(s)	Contino, Roberto (CERN ; ITPP, Lausanne) ; Salvarezza, Matteo (INFN, Rome ; Rome U.)
Publication	2015-12-14
Imprint	02 Nov 2015
Number of pages	16
Note	Comments: 34 pages, 4 figures 34 pages, 4 figures. v2: a few minor changes, typos corrected, list of references revised
In:	Phys. Rev. D 92 (2015) 115010
DOI	10.1103/PhysRevD.92.115010
Subject category	Particle Physics - Phenomenology
Abstract	We derive dispersion relations for the electroweak oblique observables measured at LEP in the context of $SO(5)/SO(4)$ composite Higgs models. It is shown how these relations can be used and must be modified when modeling the spectral functions through a low-energy effective description of the strong dynamics. The dispersion relation for the parameter $\epsilon_3$ is then used to estimate the contribution from spin-1 resonances at the 1-loop level. Finally, it is shown that the sign of the contribution to the $\hat S$ parameter from the lowest-lying spin-1 states is not necessarily positive definite, but depends on the energy scale at which the asymptotic behavior of current correlators is attained.
Copyright/License	arXiv nonexclusive-distrib. 1.0 preprint: © 2015-2024 CERN (License: CC-BY-4.0) publication: © 2015-2024 The Author(s) (License: CC-BY-3.0)

Corresponding record in: Inspire