Probing top-quark couplings indirectly at Higgs factories

Abstract

We perform a global effective-field-theory analysis to assess the combined precision on Higgs couplings, triple gauge-boson couplings, and top-quark couplings, at future circular $e^{+}{e}^{-}$ colliders, with a focus on runs below the $t\bar{t}$ production threshold. Deviations in the top-quark sector entering as one-loop corrections are consistently taken into account in Higgs and diboson processes. We find that future lepton colliders running at center-of-mass energies below the $t\bar{t}$ production threshold can still provide useful information on top-quark couplings, by measuring virtual top-quark effects. With rate and differential measurements, the indirect individual sensitivity achievable is better than at the high-luminosity LHC. However, strong correlations between the extracted top-quark and Higgs couplings are also present and lead to much weaker global constraints on top-quark couplings. This implies that a direct probe of top-quark couplings above the $t\bar{t}$ production threshold is helpful also for the determination of Higgs and triple-gauge-boson couplings. In addition, we find that below the $e^{+}{e}^{-}\to t\bar{t}h$ production threshold, the top-quark Yukawa coupling can be determined by its loop corrections to all Higgs production and decay channels. Degeneracy with the $ggh$ coupling can be resolved, and even a global limit is competitive with the prospects of a linear collider above the threshold. This provides an additional means of determining the top-quark Yukawa coupling indirectly at lepton colliders.

14 pages, 6 figures, v2: minor changes, matches the published version

References in corpus (14)

• 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
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Higgs production in association with a top-antitop pair in the Standard Model Effective Field Theory at NLO in QCD
• A global view on the Higgs self-coupling at lepton colliders
• On the maximal use of Monte Carlo samples: re-weighting events at NLO accuracy
• Higgs Decays to $ZZ$ and $Z\gamma$ in the SMEFT: an NLO analysis
• Dimension-six electroweak top-loop effects in Higgs production and decay
• Anomalous Higgs couplings in angular asymmetries of H --> Zl+l- and e+e- --> HZ
• The decay $h\to \gamma \gamma$ in the Standard-Model Effective Field Theory
• QCD radiative corrections for $h\to b\bar{b}$ in the Standard Model Dimension-6 EFT
• Implications of CP-violating Top-Higgs Couplings at LHC and Higgs Factories
• Measuring the top Yukawa coupling at the ILC at sqrt(s) = 500 GeV
• Probing 6D Operators at Future $e^{-}{e}^{+}$ Colliders

Cited by in corpus (23)

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• On the future of Higgs, electroweak and diboson measurements at lepton colliders
• Electroweak and QCD Corrections to $Z$ and $W$ pole observables in the SMEFT
• The electro-weak couplings of the top and bottom quarks -- global fit and future prospects
• Top and Beauty synergies in SMEFT-fits at present and future colliders
• Constraining top-quark couplings combining top-quark and $\mathbf{B}$ decay observables
• Quantum tops at circular lepton colliders
• SMEFTs living on the edge: determining the UV theories from positivity and extremality
• The top quark electro-weak couplings after LHC Run 2
• Gauge Invariance and Finite Counterterms in Chiral Gauge Theories
• Correlating uncertainties in global analyses within SMEFT matters
• Probing Top-quark Operators with Precision Electroweak Measurements
• A Note on Gauge Anomaly Cancellation in Effective Field Theories
• Optimal determination of New Physics couplings: A comparative study
• Searching for pseudo Nambu-Goldstone boson dark matter production in association with top quarks
• Constraining New Physics with Single Top production at LHC
• Investigating Bottom-Quark Yukawa Interaction at Higgs Factory
• Constraining the top quark effective field theory using the top quark pair production in association with a jet at future lepton colliders
• Probing Z/W Pole Physics at High-energy Muon Colliders via Vector-boson-fusion Processes
• Tracing the bottom electroweak dipole operators at future lepton colliders
• Single-spin measurements and heavy new physics in the $e^{+}{e}^{-}\to t\bar{t}$ process at an FCC-ee