Search for the flavor-changing neutral current interactions of the top quark and the Higgs boson which decays into a pair of b quarks at √s = 13 TeV

Abstract

A search for avor-changing neutral currents (FCNC) in events with the top quark and the Higgs boson is presented. The Higgs boson decay to a pair of b quarks is considered. The data sample corresponds to an integrated luminosity of 35:9 fbð€€€1 recorded by the CMS experiment at the LHC in proton-proton collisions at p s = 13TeV. Two channels are considered: single top quark FCNC production in association with the Higgs boson (pp ! tH), and top quark pair production with FCNC decay of the top quark (t ! qH). Final states with one isolated lepton and at least three reconstructed jets, among which at least two are associated with b quarks, are studied. No signi cant deviation is observed from the predicted background. Observed (expected) upper limits at 95% con dence level are set on the branching fractions of top quark decays, B(t ! uH) < 0:47% (0:34%) and B(t ! cH) < 0:47% (0:44%), assuming a single nonzero FCNC coupling.