Measurements of ttH production and the CP structure of the Yukawa interaction between the Higgs boson and top quark in the diphoton decay channel
17 AUG 2020
11:00 - 12:00
Based on : 2003.10866 [hep-ex].
Abstract: The first observation of the ttH process in a single Higgs boson decay channel with the full reconstruction of the final state (H → γγ) is presented, with a significance of 6.6 standard deviations (σ). The CP structure of Higgs boson couplings to fermions is measured, resulting in an exclusion of the pure CP-odd structure of the top Yukawa coupling at 3.2σ. The measurements √ are based on a sample of proton-proton collisions at a center-of-mass energy s = 13 TeV collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb − 1. The cross-section times 0.34 branching fraction of the ttH process is measured to be σ tt H B γγ = 1.56 +− 0.32 fb, which + 0.08 is compatible with the standard model prediction of 1.13 − 0.11 fb. The fractional contribution of the CP-odd component is measured to be f CP = 0.00 ± 0.33.