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arXiv · 1307.0496

Precision Higgs Measurements: Constraints from New Oblique Corrections

Abstract

New particles entering into self-energies of the Higgs boson would necessarily modify loop-induced couplings of the Higgs, if the new particle carries standard model gauge quantum numbers. For a 1 TeV new particle, deviations in these "Higgs oblique corrections" are generically of the order of v^2/(1 TeV)^2 ~ 5%. We study constraints on masses and couplings of new scalars and fermions that can be derived from 5-10% deviations in the Higgs digluon and diphoton partial widths. To reduce theoretical uncertainties, we present next-to-leading order QCD corrections to the Higgs-to-digluon coupling for scalars and fermions in arbitrary representations of SU(3) color group, by applying the low-energy Higgs theorems at two-loop order. As a by-product we provide a new value for NLO QCD corrections to the top squark contributions to digluon decays that differs from existing literature. We also emphasize that precise measurements of Higgs couplings to W boson and top quark are prerequisite to precise determinations of Higgs oblique corrections from new particles.

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BibTeXRIS

Stefania Gori, Ian Low. 2013-07-01. Precision Higgs Measurements: Constraints from New Oblique Corrections. https://doi.org/10.1007/jhep09(2013)151

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