Aad, G.Abbott, B.Abbott, D.C.Abeling, K.Abidi, S.H.Aboulhorma, A.Çetin, Serkant Ali2024-05-192024-05-1920231434-6044https://doi.org/10.1140/epjc/s10052-023-11583-yhttps://hdl.handle.net/20.500.12713/4538A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and ? -leptons is presented. The study is based on a measurement of CP -sensitive angular observables defined by the visible decay products of ? -leptons produced in Higgs boson decays. The analysis uses 139 fb- 1of proton–proton collision data recorded at a centre-of-mass energy of s=13 TeV with the ATLAS detector at the Large Hadron Collider. Contributions from CP -violating interactions between the Higgs boson and ? -leptons are described by a single mixing angle parameter ??in the generalised Yukawa interaction. Without constraining the H? ?? signal strength to its expected value under the Standard Model hypothesis, the mixing angle ??is measured to be 9?± 16?, with an expected value of 0?± 28?at the 68% confidence level. The pure CP -odd hypothesis is disfavoured at a level of 3.4 standard deviations. The results are compatible with the predictions for the Higgs boson in the Standard Model. © 2023, The Author(s).eninfo:eu-repo/semantics/openAccessMixingTellurium CompoundsAtlas DetectorsCharge ConjugationCharge-ParityDecay ProductsExpected ValuesHiggs BosonMeasurements OfMixing AnglePropertyThe Standard ModelBosonsArticle8372-s2.0-8517285938710.1140/epjc/s10052-023-11583-yN/A