Search for the flavor-changing interactions of the top quark with the Higgs boson in $H \to b\bar{b}$ channel at $\sqrt{s}=13~\mathrm{TeV}$

A search for flavor-changing neutral currents (FCNC) in associated production of a top quark with a Higgs boson is presented. Two channels are considered: top quark pair production, with FCNC decay of the top quark or antiquark, and single top production ($pp \to tH$). This is the first analysis to probe top-Higgs FCNC couplings in the single top production mode. A final state with one isolated lepton and at least three reconstructed jets, among which at least two are identified as b quark jets, is studied. The data sample corresponds to an integrated luminosity of $35.9~\mathrm{fb}^{-1}$ recorded by the CMS experiment at the LHC in proton-proton collisions at $\sqrt{s}=13~\mathrm{TeV}$ in 2016. No significant deviation is observed from predicted background. Observed (expected) upper limits at $95\%$ confidence level are set on the branching ratios of top quark decays, $B(t \rightarrow u H) < 0.47\%~(0.34\%)$ and $B(t \rightarrow c H) < 0.47\%~(0.44\%)$, assuming a single non-vanishing FCNC coupling.