Measurement of the t t Z and t t W cross sections in proton-proton collisions at s =13 TeV with the ATLAS detector

A measurement of the associated production of a top-quark pair (tt) with a vector boson (W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented, using 36.1 fb-1 of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. Events are selected in...

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Detalles Bibliográficos
Autores: Álvarez Piqueras, D., Aparisi Pozo, J.A., Bailey, A.J., Barranco, Laura, Cabrera, Susana, Castillo, F.L., Castillo Gimenez, M. V., Cerda Alberich, L., Costa, María José, Escobar, Carlos, Estrada, Oscar, Ferrer, Antonio, Fiorini, L., Fullana, Esteban, Fuster, Juan, García García, Carmen, García Navarro, José Enrique, González de la Hoz, Santiago, Higón, Emilio, Jimenez Pena, Javier, Lacasta Llácer, Carlos, Lozano Bahilo, José J., Madaffari, Daniele, Mamuzic, Judita, Martí García, Salvador, Melini, Davide, Miñano Moya, M., Mitsou, Vasiliki A., Rodriguez Bosca, S., Rodriguez Rodriguez, D., Ruiz Martínez, Arantxa, Salt, José, Santra, A., Sánchez Martínez, Javier, Soldevila, Urmila, Valero, Alberto, Valls Ferrer, Juan Antonio, Vos, Marcel, ATLAS Collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/195868
Acceso en línea:http://hdl.handle.net/10261/195868
Access Level:acceso abierto
Palabra clave:ddc:500.2
Descripción
Sumario:A measurement of the associated production of a top-quark pair (tt) with a vector boson (W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented, using 36.1 fb-1 of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. Events are selected in channels with two same- or opposite-sign leptons (electrons or muons), three leptons or four leptons, and each channel is further divided into multiple regions to maximize the sensitivity of the measurement. The ttZ and ttW production cross sections are simultaneously measured using a combined fit to all regions. The best-fit values of the production cross sections are σttZ=0.95±0.08stat±0.10syst pb and σttW=0.87±0.13stat±0.14syst pb in agreement with the Standard Model predictions. The measurement of the ttZ cross section is used to set constraints on effective field theory operators which modify the ttZ vertex.