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arXiv · 1306.4644

Electroweak Precision Observables, New Physics and the Nature of a 126 GeV Higgs Boson

Marco Ciuchini·Enrico Franco·Satoshi Mishima·Luca Silvestrini
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Abstract

We perform the fit of electroweak precision observables within the Standard Model with a 126 GeV Higgs boson, compare the results with the theoretical predictions and discuss the impact of recent experimental and theoretical improvements. We introduce New Physics contributions in a model-independent way and fit for the S, T and U parameters, for the $ε_{1,2,3,b}$ ones, for modified $Zb\bar{b}$ couplings and for a modified Higgs coupling to vector bosons. We point out that composite Higgs models are very strongly constrained. Finally, we compute the bounds on dimension-six operators relevant for the electroweak fit.

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Marco Ciuchini, Enrico Franco, Satoshi Mishima, Luca Silvestrini. 2013-08-22. Electroweak Precision Observables, New Physics and the Nature of a 126 GeV Higgs Boson. https://doi.org/10.1007/jhep08(2013)106

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