%0 Journal Article
%T Evidence for the associated production of the Higgs boson and a top quark pair with the ATLAS detector
%A ATLAS Collaboration (Aaboud, M. et al
%A Alvarez Piqueras, D.
%A Barranco Navarro, L.
%A Cabrera Urban, S.
%A Castillo Gimenez, V.
%A Cerda Alberich, L.
%A Costa, M. J.
%A Escobar, C.
%A Estrada Pastor, O.
%A Fernandez Martinez, P.
%A Ferrer, A.
%A Fiorini, L.
%A Fuster, J.
%A Garcia, C.
%A Garcia Navarro, J. E.
%A Gonzalez de la Hoz, S.
%A Higon-Rodriguez, E.
%A Jimenez Pena, J.
%A Lacasta, C.
%A Madaffari, D.
%A Mamuzic, J.
%A Marti-Garcia, S.
%A Melini, D.
%A Mitsou, V. A.
%A Pedraza Lopez, S.
%A Rodriguez Bosca, S.
%A Rodriguez Rodriguez, D.
%A Romero Adam, E.
%A Salt, J.
%A Soldevila, U.
%A Sanchez, J.
%A Valero, A.
%A Valls Ferrer, J. A.
%A Vos, M.
%J Physical Review D
%D 2018
%V 97
%N 7
%I Amer Physical Soc
%@ 2470-0010
%G English
%F ATLASCollaborationAaboud_etal2018
%O WOS:000429456900001
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3556), last updated on Wed, 25 Apr 2018 09:25:08 +0000
%X A search for the associated production of the Higgs boson with a top quark pair ((tt) over barH) is reported. The search is performed in multilepton final states using a data set corresponding to an integrated luminosity of 36.1 fb(-1) of proton-proton collision data recorded by the ATLAS experiment at a center-of-mass energy root s = 13 TeV at the Large Hadron Collider. Higgs boson decays to WW*, tau tau, and ZZ* are targeted. Seven final states, categorized by the number and flavor of charged-lepton candidates, are examined for the presence of the Standard Model Higgs boson with a mass of 125 GeVand a pair of top quarks. An excess of events over the expected background from Standard Model processes is found with an observed significance of 4.1 standard deviations, compared to an expectation of 2.8 standard deviations. The best fit for the (tt) over barH production cross section is sot (tt) over barH) = 790(-210)(+230) fb, in agreement with the Standard Model prediction of 507(-50)(+35) fb. The combination of this result with other t <overline> tH searches from the ATLAS experiment using the Higgs boson decay modes to b (b) over bar, gamma gamma and ZZ* -> 4l, has an observed significance of 4.2 standard deviations, compared to an expectation of 3.8 standard deviations. This provides evidence for the (tt) over barH production mode.
%R 10.1103/PhysRevD.97.072003
%U http://arxiv.org/abs/1712.08891
%U https://doi.org/10.1103/PhysRevD.97.072003
%P 072003-44pp