CERN Accelerating science

ATLAS Note
Report number	ATLAS-CONF-2022-016
Title	Probing the $CP$ nature of the top-Higgs Yukawa coupling in $t\bar{t}H$ and $tH$ events with $H \rightarrow b\bar{b}$ using the ATLAS detector at the LHC
Corporate Author(s)	The ATLAS collaboration
Collaboration	ATLAS Collaboration
Publication	2022
Imprint	03 Apr 2022
Number of pages	mult.
Note	All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2022-016
In:	56th Rencontres de Moriond on QCD and High Energy Interactions, La Thuile, Italy, 19 - 26 Mar 2022
Subject category	Particle Physics - Experiment
Accelerator/Facility, Experiment	CERN LHC ; ATLAS
Abstract	This note presents an investigation of the $CP$ properties of the coupling between the Higgs boson and the top quark, employing 139 fb$^{-1}$ of proton--proton collision data recorded by the ATLAS experiment at a centre-of-mass energy of $\sqrt{s}=13$ TeV. The $CP$ structure of the top-Higgs boson Yukawa coupling is probed in events with a Higgs boson decaying to a pair of $b$ quarks and produced in association with a pair of top quarks, $t\bar{t}H$, or a single top quark, $tH$. Events containing one or two electrons or muons are used for the measurement. In an extension of the Standard Model with a CP-odd admixture to the top-Higgs Yukawa coupling, the mixing angle between $CP$-even and $CP$-odd couplings is measured to be $\alpha=11^{\circ+55^{\circ}}_{ -77^{\circ}}$. A pure $CP$-odd coupling is disfavoured by the data at 1.2$\sigma$ confidence level.
Related document	superseded by: CERN-EP-2022-208

Corresponding record in: Inspire