Probing the CP properties of top Yukawa coupling at an $e^{+}{e}^{-}$ collider

Abstract

We study consequences of CP violation in the $ht\bar{t}$ Yukawa coupling through the process $e^{+}{e}^{-}\to$ $h(125)t\bar{t}$. The helicity amplitudes are calculated in the $t\bar{t}$ rest frame, where the initial $e^{+}{e}^{-}$ current and the final Higgs boson have the same three-momentum. CP-violating asymmetries appear not only in the azimuthal angle between the $e^{+}{e}^{-}$ plane and the $t\bar{t}$ plane about the Higgs momentum direction, but also in the correlated decay angular distributions of $t$ and $\bar{t}$. Complete description of the production and decay angular distributions are obtained analytically, including both leptonic and hadronic decays of $t$ and $\bar{t}$. We study the ultimate sensitivity to the CP-violating $ht\bar{t}$ coupling at a few center-of-mass energies. Our analysis shows that the possibility of discovering CP violating $ht\bar{t}$ coupling improves significantly by studying $t\bar{t}$ decay angular correlations, and more importantly, by increasing its energy upgrade target from $\sqrt{s}=500$ GeV to 550 GeV.

28 pages, 14 figures, 4 tables; references added, version accepted by JHEP

References in corpus (9)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Measurements of the Higgs boson production and decay rates and coupling strengths using $pp$ collision data at $\sqrt{s}=7$ and $8$ TeV in the ATLAS experiment
• Higgs characterisation at NLO in QCD: CP properties of the top-quark Yukawa interaction
• Boosting the Direct CP Measurement of the Higgs-Top Coupling
• Determining the CP properties of the Higgs boson
• Exploring the Anomalous Higgs-top Couplings
• Measuring the top Yukawa coupling at the ILC at sqrt(s) = 500 GeV
• Probing Higgs Boson $CP$ Properties with $t\bar{t}H$ at the LHC and the 100 TeV $pp$ Collider
• Next-to-leading-logarithmic QCD Corrections to the Cross Section sigma(e+e- to t bar t H) at 500 GeV

Cited by in corpus (12)

• Probing the Top-Higgs Yukawa CP Structure in dileptonic $t\bar{t}h$ with $M_2$-Assisted Reconstruction
• Signatures of toponium formation in LHC run 2 data
• Two-Higgs-Doublet Model with Soft CP-violation Confronting Electric Dipole Moments and Colliders
• Aligned CP-violating Higgs sector canceling the electric dipole moment
• Collapsing domain walls in the two-Higgs-doublet model and deep insights from the EDM
• Simulating toponium formation signals at the LHC
• Probing the Higgs Yukawa coupling to the top-quark at the LHC via single top + Higgs production
• Boosted Top quark polarization
• Probing the CP Structure of the Top Quark Yukawa at the Future Muon Collider
• Probing the top Yukawa coupling at the LHC via associated production of single top and Higgs
• T-odd anomalous interactions of the top-quark at the Large Hadron Collider
• Testing CP-violation in a Heavy Higgs Sector at CLIC