Interplay between new physics in one-loop Higgs couplings and the top-quark Yukawa coupling

Abstract

After the discovery of a 126 GeV state at the LHC it is imperative to establish whether this particle really is the Higgs boson of the standard model. The early measurements have not yet pinpointed any of the Higgs couplings to fermions, the Yukawa couplings of the standard model. In this paper we study the values of the top-quark-Higgs coupling, $g_{ht\bar{t}}$, that are still allowed by the one-loop couplings of the Higgs to two gluons or two photons. We first assume that both the gluon fusion production of the Higgs and its decay into two photons proceed through loops with standard model particles only, albeit with an arbitrary top-Higgs coupling. We find that the current Higgs data still allows for 20% deviations in $g_{ht\bar{t}}$ from its standard model value. We then investigate the effect of new particles contributing to the effective one-loop couplings. Specifically we consider a color octet electroweak doublet extension of the scalar sector and find that in this case $g_{ht\bar{t}}$ is allowed to deviate by 40% from its standard model value by the current data.

14 pages, 5 figures

References in corpus (17)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Flavor Changing Neutral Currents, an Extended Scalar Sector, and the Higgs Production Rate at the LHC
• Updated Global Analysis of Higgs Couplings
• Higgs Precision (Higgcision) Era begins
• A Bayesian view of the Higgs sector with higher dimensional operators
• Color-octet scalars at the LHC
• Single top and Higgs associated production as a probe of the Htt coupling sign at the LHC
• Color Octet Scalar Production at the LHC
• Constraining extra-fermion(s) from the Higgs boson data
• New Higgs interactions and recent data from the LHC and the Tevatron
• New Scalar Contributions to $h\to Z\gamma$
• Search for the standard model Higgs boson produced in association with a top-quark pair in pp collisions at the LHC
• Early Higgs Hints for Non-Minimal Supersymmetry
• Higgs Uncovering Light Scalar Remnants of High Scale Matter Unification
• Unitarity and vacuum stability constraints on the couplings of color octet scalars
• Inspecting the Higgs for New Weakly Interacting Particles

Cited by in corpus (12)

• Enhanced $thj$ signal at the LHC with $h\to \gamma \gamma$ decay and $\mathcal{C}\mathcal{P}$-violating top-Higgs coupling
• Probing Higgs Boson $CP$ Properties with $t\bar{t}H$ at the LHC and the 100 TeV $pp$ Collider
• Precision Higgs Measurements: Constraints from New Oblique Corrections
• LHC constraints on color octet scalars
• Two Higgs doublet models augmented by a scalar color octet
• Top and bottom tensor couplings from a color octet scalar
• Color-octet scalar decays to a gluon and an electroweak gauge boson in the Manohar-Wise model
• Improving the measurement of the Higgs boson-gluon coupling using convolutional neural networks at $e^{+}{e}^{-}$ colliders
• Probing the Higgs boson-gluon coupling via the jet energy profile at $e^{+}{e}^{-}$ colliders
• Top polarisation as a probe of CP-mixing top-Higgs coupling in $tjh$ signals
• Fingerprinting the contribution of colored scalars to the $H^{+}{W}^{-}Z(\gamma )$ vertex
• Colour Octet Extension of 2HDM