TY - JOUR AU - ATLAS Collaboration (Aaboud, M. et al AU - Alvarez Piqueras, D. AU - Bailey, A. J. AU - Barranco Navarro, L. AU - Cabrera Urban, S. AU - Castillo, F. L. AU - Castillo Gimenez, V. AU - Cerda Alberich, L. AU - Costa, M. J. AU - Escobar, C. AU - Estrada Pastor, O. AU - Ferrer, A. AU - Fiorini, L. AU - Fullana Torregrosa, E. AU - Fuster, J. AU - Garcia, C. AU - Garcia Navarro, J. E. AU - Gonzalez de la Hoz, S. AU - Higon-Rodriguez, E. AU - Jimenez Pena, J. AU - Lacasta, C. AU - Lozano Bahilo, J. J. AU - Madaffari, D. AU - Mamuzic, J. AU - Marti-Garcia, S. AU - Melini, D. AU - Miñano, M. AU - Mitsou, V. A. AU - Rodriguez Bosca, S. AU - Rodriguez Rodriguez, D. AU - Ruiz-Martinez, A. AU - Salt, J. AU - Santra, A. AU - Soldevila, U. AU - Sanchez, J. AU - Valero, A. AU - Valls Ferrer, J. A. AU - Vos, M. PY - 2018 DA - 2018// TI - Observation of Higgs boson production in association with a top quark pair at the LHC with the ATLAS detector T2 - Phys. Lett. B JO - Physics Letters B SP - 173 EP - 191 VL - 784 PB - Elsevier Science Bv AB - The observation of Higgs boson production in association with a top quark pair (t (t) over barH), based on the analysis of proton-proton collision data at a centre-of-mass energy of 13 TeV recorded with the ATLAS detector at the Large Hadron Collider, is presented. Using data corresponding to integrated luminosities of up to 79.8 fb(-1), and considering Higgs boson decays into b (b) over bar, WW*, tau(+)tau(-), gamma gamma, and ZZ*, the observed significance is 5.8 standard deviations, compared to an expectation of 4.9 standard deviations. Combined with the t (t) over barH searches using a dataset corresponding to integrated luminosities of 4.5 fb(-1) at 7 TeV and 20.3 fb(-1) at 8 TeV, the observed (expected) significance is 6.3 (5.1) standard deviations. Assuming Standard Model branching fractions, the total t (t) over barH production cross section at 13 TeV is measured to be 670 +/- 90(stat.)(-100)(+110)(syst.) fb, in agreement with the Standard Model prediction. SN - 0370-2693 UR - http://arxiv.org/abs/1806.00425 UR - https://doi.org/10.1016/j.physletb.2018.07.035 DO - 10.1016/j.physletb.2018.07.035 LA - English N1 - WOS:000445781600029 ID - ATLASCollaborationAaboud_etal2018 ER -