2020/04/30 by ATLAS Collaboration, G. Aad, B. Abbott +97 · 1 citation
Physics and Astronomy · #Higgs boson #High-Energy Particle Collisions Research #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1103/physrevlett.125.061802
published as Phys. Rev. Lett. 125, 061802 (2020) · 29 pages in total, author list starting page 13, 3 figures, no tables, published in Phys. Rev. Lett. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HIGG-2019-01/
openalex publication_date 2020/08/05 · arxiv created 2020/08/08 · arxiv updated 2020/08/12 · openalex created_date 2020/08/13 · openalex updated_date 2026/08/06
A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H\ensuremath→\ensuremathγ\ensuremathγ), and their production in association with a top quark pair (ttH) or single top quark (tH) is studied. The analysis uses 139 fb^\ensuremath-1 of proton--proton collision data recorded at a center-of-mass energy of √(s)=13 TeV with the ATLAS detector at the Large Hadron Collider. Assuming a CP-even coupling, the ttH process is observed with a significance of 5.2 standard deviations. The measured cross section times H\ensuremath→\ensuremathγ\ensuremathγ branching ratio is 1.64_\ensuremath-0.36+0.38(stat)_\ensuremath-0.14+0.17(sys) fb, and the measured rate for ttH is 1.43_\ensuremath-0.31+0.33(stat)_\ensuremath-0.15+0.21(sys) times the Standard Model expectation. The tH production process is not observed and an upper limit on its rate of 12 times the Standard Model expectation is set. A CP-mixing angle greater (less) than 43 (\ensuremath-43)\ifmmode^∘\else\textdegree\fi is excluded at 95% confidence level.