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arXiv · 1412.6038

Pseudo-observables in Higgs decays

Martin Gonzalez-Alonso·Admir Greljo·Gino Isidori·David Marzocca
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Abstract

We define a set of pseudo-observables characterizing the properties of Higgs decays in generic extensions of the Standard Model with no new particles below the Higgs mass. The pseudo-observables can be determined from experimental data, providing a systematic generalization of the "kappa-framework" so far adopted by the LHC experiments. The pseudo-observables are defined from on-shell decay amplitudes, allow for a systematic inclusion of higher-order QED and QCD corrections, and can be computed in any Effective Field Theory (EFT) approach to Higgs physics. We analyze the reduction of the number of independent pseudo-observables following from the hypotheses of lepton-universality, CP invariance, custodial symmetry, and linearly realized electroweak symmetry breaking. We outline the importance of kinematical studies of $h\to 4\ell$ decays for the extraction of such parameters and present their predictions in the linear EFT framework.

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Martin Gonzalez-Alonso, Admir Greljo, Gino Isidori, David Marzocca. 2015-03-13. Pseudo-observables in Higgs decays. https://doi.org/10.1140/epjc%2Fs10052-015-3345-5

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