Measurements of&lt;em&gt; tt&lt;sup&gt;-&lt;/sup&gt;H&lt;/em&gt; production and the &lt;em&gt;CP&lt;/em&gt; structure of the Yukawa interaction between the Higgs boson and top quark in the diphoton decay channel

Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Bergauer, T.; Dragicevic, M.; Erö, J.; Escalante Del Valle, A.; Flechl, M.; Frühwirth, R.; Caminada, L.; Deiters, K.; Erdmann, W.; Horisberger, R.; Ingram, Q.; Kaestli, H.C.; Kotlinski, D.; Langenegger, U.; Rohe, T.; Vetens, W.

doi:10.1103/PhysRevLett.125.061801

Measurements of tt^-H production and the CP structure of the Yukawa interaction between the Higgs boson and top quark in the diphoton decay channel

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Bergauer T, Dragicevic M, Erö J, Escalante Del Valle A, Flechl M, Frühwirth R, Caminada L, Deiters K, Erdmann W, Horisberger R, Ingram Q, Kaestli HC, Kotlinski D, Langenegger U, Rohe T, Vetens W, et al.

Citation

Sirunyan, A. M., Tumasyan, A., Adam, W., Ambrogi, F., Bergauer, T., Dragicevic, M., … Vetens, W. (2020). Measurements of tt^-H production and the CP structure of the Yukawa interaction between the Higgs boson and top quark in the diphoton decay channel. Physical Review Letters, 125(6), 061801 (18 pp.). https://doi.org/10.1103/PhysRevLett.125.061801

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:34283

The first observation of the tt^-H 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 branching fraction of the t¯tH process is measured to be σ_t¯tHB_γγ=1.56^+0.34_−0.32 fb, which is compatible with the standard model prediction of 1.13^+0.08_−0.11 fb. The fractional contribution of the CP-odd component is measured to be f^Htt_CP= 0.00 ± 0.33.