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arXiv · 2304.09612

Test of CP-invariance of the Higgs boson in vector-boson fusion production and its decay into four leptons

ATLAS Collaboration
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Abstract

A search for CP violation in the decay kinematics and vector-boson production of the Higgs boson is performed in the $H \to ZZ^{*} \to 4\ell$ ($\ell = e,\mu$) decay channel. The results are based on proton-proton collision data produced at the LHC at a centre-of-mass energy of 13 TeV and recorded by the ATLAS detector from 2015 to 2018, corresponding to an integrated luminosity of 139 $\mbox{fb\(^{-1}\)}$. Matrix element-based optimal observables are used to constrain CP-odd couplings beyond the Standard Model in the framework of Standard Model effective field theory expressed in the Warsaw and Higgs bases. Differential fiducial cross-section measurements of the optimal observables are also performed, and a new fiducial cross-section measurement for vector-boson-fusion production is provided. All measurements are in agreement with the Standard Model prediction of a CP-even Higgs boson.

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ATLAS Collaboration. 2023-04-19. Test of CP-invariance of the Higgs boson in vector-boson fusion production and its decay into four leptons. https://doi.org/10.1007/jhep05(2024)105

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