Measurements of (tt)over-barH Production and the CP Structure of the Yukawa Interaction between the Higgs Boson and Top Quark in the Diphoton Decay Channel
PHYSICAL REVIEW LETTERS, cilt.125, sa.6, 2020 (SCI-Expanded)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 125 Sayı: 6
- Basım Tarihi: 2020
- Doi Numarası: 10.1103/physrevlett.125.061801
- Dergi Adı: PHYSICAL REVIEW LETTERS
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Compendex, EMBASE, INSPEC, MEDLINE, zbMATH, DIALNET
- Çukurova Üniversitesi Adresli: Evet
Özet
The first observation of the (tt) over barH process in a single Higgs boson decay channel with the full reconstruction of the final state (H -> gamma gamma) is presented, with a significance of 6.6 standard deviations (sigma). 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 3.2 sigma. The measurements are based on a sample of protonproton collisions at a center-of-mass energy root s = 13 TeV collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb(-1). The cross section times branching fraction of the (tt) over barH process is measured to be sigma B-(tt) over barH(gamma gamma) = 1.56(-0.32)(+0.34) th, which is compatible with the standard model prediction of 1.13(-0.11)(+0.08) fb. The fractional contribution of the CP-odd component is measured to be f(CP)(Hu) = 0.00 +/- 0.33.