Search for CPCP Violation in ttH and tH Production in Multilepton Channels in Proton-Proton Collisions at √s = 13 TeV
Journal of High Energy Physics 2023
Kārlis Dreimanis, Antra Gaile, Andris Potrebko, Toms Torims, Viesturs Veckalns, CMS Collaboration

The charge-parity (CP) structure of the Yukawa interaction between the Higgs (H) boson and the top quark is measured in a data sample enriched in the tt‾tH and tH associated production, using 138 fb−1−1 of data collected in proton-proton collisions at ss ​ = 13 TeV by the CMS experiment at the CERN LHC. The study targets events where the H boson decays via H → WW or H → ττ and the top quarks decay via t → Wb: the W bosons decay either leptonically or hadronically, and final states characterized by the presence of at least two leptons are studied. Machine learning techniques are applied to these final states to enhance the separation of CP -even from CP -odd scenarios. Two-dimensional confidence regions are set on κtt​ and κ∼tκ∼t​, which are respectively defined as the CP -even and CP -odd top-Higgs Yukawa coupling modifiers. No significant fractional CP -odd contributions, parameterized by the quantity |fCPHttfCPHtt​| are observed; the parameter is determined to be |fCPHttfCPHtt​| = 0.59 with an interval of (0.24, 0.81) at 68% confidence level. The results are combined with previous results covering the H → ZZ and H → γγ decay modes, yielding two- and one-dimensional confidence regions on κtt​ and κ∼tκ∼t​, while |fCPHttfCPHtt​| is determined to be |fCPHttfCPHtt​| = 0.28 with an interval of |fCPHttfCPHtt​| < 0.55 at 68% confidence level, in agreement with the standard model CP -even prediction of |fCPHttfCPHtt​| = 0.


Atslēgas vārdi
CP Violation, Hadron-Hadron Scattering, Higgs Physics
DOI
10.1007/JHEP07(2023)092
Hipersaite
https://link.springer.com/article/10.1007/JHEP07(2023)092

The CMS Collaboration, A.Tumasyan, K.Dreimanis, A.Gaile, A.Potrebko, T.Torims, V.Veckalns ... [et al.]. Search for CPCP Violation in ttH and tH Production in Multilepton Channels in Proton-Proton Collisions at √s = 13 TeV. Journal of High Energy Physics, 2023, Vol. 2023, No. 7, Article number 92. e-ISSN 1029-8479. Available from: doi:10.1007/JHEP07(2023)092

Publikācijas valoda
English (en)
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