Search for heavy particles decaying into top-quark pairs using lepton-plus-jets events in proton–proton collisions at $\sqrt{s} = 13$   $\text {TeV}$ with the ATLAS detector

• Autor(a) principal: ATLAS collaboration (2891 authors)
• Data de Publicação: 2018
• Outros Autores: Aguilar Saavedra, Juan Antonio, Amor Dos Santos, Susana Patricia, Araque Espinosa, Juan Pedro, Castro, Nuno Filipe, Conde Muino, Patricia, Da Cunha Sargedas De Sousa, Mario Jose, Dias DO Vale, Tiago, Faisca Rodrigues Pereira, Rui Miguel, Fiolhais, Miguel, Galhardo, Bruno, Gomes, Agostinho, Goncalo, Ricardo, Jorge, Pedro, Machado Miguens, Joana, Maio, Amelia, Maneira, Jose, Oleiro Seabra, Luis Filipe, Onofre, Antonio, Costa Batalha Pedro, Rute, Pereira Peixoto, Ana Paula, Santos, Helena, Saraiva, Joao, Silva, Jose Manuel, Tavares Delgado, Ademar, Veloso, Filipe, Wolters, Helmut
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.26/27624

A search for new heavy particles that decay into top-quark pairs is performed using data collected from proton–proton collisions at a centre-of-mass energy of 13  $\text {TeV}$ by the ATLAS detector at the Large Hadron Collider. The integrated luminosity of the data sample is 36.1 fb$^{-1}$ . Events consistent with top-quark pair production are selected by requiring a single isolated charged lepton, missing transverse momentum and jet activity compatible with a hadronic top-quark decay. Jets identified as likely to contain b-hadrons are required to reduce the background from other Standard Model processes. The invariant mass spectrum of the candidate top-quark pairs is examined for local excesses above the background expectation. No significant deviations from the Standard Model predictions are found. Exclusion limits are set on the production cross-section times branching ratio for hypothetical $Z'$ bosons, Kaluza–Kein gluons and Kaluza–Klein gravitons that decay into top-quark pairs.