The Minimal Composite Higgs Model and Electroweak Precision Tests

By K. Agashe, Roberto Contino. 2005

220 citations recorded by the source corpus.

Abstract A complete analysis of the electroweak precision observables is performed within a recently proposed minimal composite Higgs model, realized as a 5-dimensional warped compactification. In particular, we compute Z → b b ¯ and the one-loop correction to the ρ parameter. We find that oblique data can be easily reproduced without a significant amount of tuning in the parameters of the model, while Z → b b ¯ imposes a stronger constraint. As a consequence of the latter, some of the new fermionic resonances must have mass around 4 TeV, which corresponds to an electroweak fine tuning of a few percent. Other resonances, such as Z ′ , can be lighter in sizeable portions of the parameter space. We discuss in detail the origin of the Z → b b ¯ constraint and we suggest several possible avenues beyond the minimal model for weakening it.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/e3687cdbf6c67d75aff7d061ceaac558a7d3d139

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Citations in the corpus

Physics at a 100 TeV pp collider: Higgs and EW symmetry breaking studies (2016, methodology): “The simplest realistic realization of the composite Higgs idea is represented by G = SO(5)× U(1)X and G′ = SO(4) × U(1)X and called the Minimal Composite Higgs Model (MCHM) [442, 443].”
Composite Higgs boson pair production at the LHC (2010, background): “4 This leads to an upper bound on the compositeness parameter of � 52 ].”
The flavor of the composite pseudo-goldstone Higgs (2008, methodology): “Apart from yielding the correct electroweak breaking vacuum, phenomenologically acceptable GHU models must pass stringent electroweak precision tests [35, 27].”
Electroweak and Flavour Structure of a Warped Extra Dimension with Custodial Protection (2009, background): “This approximation is justified as physical observables depend only weakly on the exact value of kL. Recently, however, it has been observed [75] that abandoning the aim to solve the gauge hierarchy problem and allowing ekL ∼ O(103) can solve some of the generic problems of RS models and allow for a”
Electroweak constraints on flavorful effective theories (2015, background): “However, the large contribution to Z → b̄LbL pushes the NP scale to the scale of order 4TeV [59].”
Fundamental composite dynamics: A review (2020, unknown): “In this effective field theory (EFT) based approach, the minimal model features the symmetry breaking pattern SO(5)/SO(4) [50, 247], under which the 4 pNGBs are enough to saturate the degrees of freedom of the Higgs doublet.”