Hayrapetyan, A.Makarenko, V.Tumasyan, A.Adam, W.Andrejkovic, J. W.Benato, L.Snigirev, A.Perely,2026-03-152026-03-1520260031-90071079-711410.1103/9nwb-splkhttps://doi.org/10.1103/9nwb-splkhttps://hdl.handle.net/20.500.14517/8895Giacomo, Bolini/0000-0001-5490-605XA search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H -> c (c) over bar, produced in association with a top quark-antiquark pair (t (t) over barH) is presented. The search is performed with data from proton-proton collisions at root s = 13 TeV, corresponding to an integrated luminosity of 138 fb(-1). Advanced machine learning techniques are employed for jet flavor identification and event classification. The Higgs boson decay to a bottom quark-antiquark pair is measured simultaneously and the observed t (t) over barH(H -> b (b) over bar) event rate relative to the standard model expectation is 0.91(+0.26)(-0.22). The observed (expected) upper limit on the product of production cross section and branching fraction sigma(t (t) over barH) B(H -> c (c) over bar) is 0.11 (0.13) pb at 95% confidence level, corresponding to 7.8 (8.7) times the standard model prediction. When combined with the previous search for H -> c (c) over bar via associated production with a W or Z boson, the observed (expected) 95% confidence interval on the Higgs-charm Yukawa coupling modifier, kappa(c), is vertical bar kappa(c)vertical bar < 3.5 (2.7), the most stringent constraint to date.eninfo:eu-repo/semantics/openAccessArticle