Probing the CP nature of the Higgs coupling in $t\bar{t}h$ events at the LHC

E. Gouveia; S. P. Amor dos Santos; M. C. N. Fiolhais; R. Frederix; R. Gonçalo; R. Martins; A. Onofre; C. M. Pease; H. Peixoto; A. Reigoto; R. Santos; J. Silva

arXiv · 1801.04954

Probing the CP nature of the Higgs coupling in $t\bar{t}h$ events at the LHC

E. Gouveia·S. P. Amor dos Santos·M. C. N. Fiolhais·R. Frederix·R. Gonçalo·R. Martins·A. Onofre·C. M. Pease·H. Peixoto·A. Reigoto·R. Santos·J. Silva

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Abstract

The determination of the CP nature of the top quark Yukawa coupling is addressed in this phenomenological work, using $t\bar{t}h$ events at the $\sqrt{s}$ = 13 TeV LHC, with $h\rightarrow b\bar b$ and through the dilepton decay channel of $t\bar{t}$. Signal events were generated for pure $CP$-even, pure $CP$-odd and mixed-$CP$ coupling scenarios. Standard Model (SM) backgrounds were also considered. Angular distributions and asymmetries were studied and found to be potentially good probes to the $CP$ nature of the coupling, even after detector simulation and full event reconstruction using a kinematic fit. Expected limits to the $t\bar th$ production cross-section times branching ratio were obtained for a range of top quark Yukawa $CP$-mixing angles and for different integrated luminosities of the LHC.

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E. Gouveia, S. P. Amor dos Santos, M. C. N. Fiolhais, R. Frederix, R. Gonçalo, R. Martins, A. Onofre, C. M. Pease, H. Peixoto, A. Reigoto, R. Santos, J. Silva. 2018-01-15. Probing the CP nature of the Higgs coupling in $t\bar{t}h$ events at the LHC. https://arxiv.org/abs/1801.04954

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