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 flavor-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 fb⁻¹ recorded by the CMS experiment at the LHC in proton-proton collisions at (\sqrt{s}=13) TeV. 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 significant deviation is observed from the predicted background. Observed (expected) upper limits at 95% confidence 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.

Description
Keywords
FCNC Interaction, Hadron-Hadron scattering (experiments), Higgs physics, Top physics
Citation
Sirunyan, A. M., Tumasyan, A., Adam, W., Ambrogi, F., Asilar, E., Bergauer, T., Brandstetter, J., Brondolin, E., Dragicevic, M., Erö, J., Escalante Del Valle, A., Flechl, M., Friedl, M., Frühwirth, R., Ghete, V. M., Grossmann, J., Hrubec, J., Jeitler, M., … Woods, N. (2018). 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 $ \sqrt{s}=13 $ TeV. In Journal of High Energy Physics (Vol. 2018, Issue 6). Springer Science and Business Media LLC. https://doi.org/10.1007/jhep06(2018)102