Chatrchyan, S.Khachatryan, V.Sirunyan, A. M.Tumasyan, A.Adam, W.Bergauer, T.The CMS Collaboration2025-03-072025-03-0720140031-90071079-7114https://doi.org/10.1103/PhysRevLett.112.171802https://hdl.handle.net/20.500.12507/2858A search for flavor-changing neutral currents in top-quark decays t -> Zq is performed in events produced from the decay chain (tt) over bar -> Zq + Wb, where both vector bosons decay leptonically, producing a final state with three leptons (electrons or muons). A data set collected with the CMS detector at the LHC is used, corresponding to an integrated luminosity of 19.7 fb(-1) of proton-proton collisions at a center-of-mass energy of 8 TeV. No excess is seen in the observed number of events relative to the standard model prediction; thus, no evidence for flavor-changing neutral currents in top-quark decays is found. A combination with a previous search at 7 TeV excludes a t. Zq branching fraction greater than 0.05% at the 95% confidence level.eninfo:eu-repo/semantics/openAccessArticle11217WOS:0003360995000032483623810.1103/PhysRevLett.112.171802Q1