Measurement of the tt¯γ production cross section in proton-proton collisions at √s = 8 TeV with the ATLAS detector

The cross section of a top-quark pair produced in association with a photon is measured in proton-proton collisions at a centre-of-mass energy of √s = 8 TeV with 20.2 fb⁻¹ of data collected by the ATLAS detector at the Large Hadron Collider in 2012. The measurement is performed by selecting events t...

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Detalles Bibliográficos
Autores: Alconada Verzini, María Josefina, Alonso, Francisco, Arduh, Francisco Anuar, Dova, María Teresa, Hoya, Joaquín, Monticelli, Fernando Gabriel, Wahlberg, Hernán Pablo, The ATLAS Collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/124804
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/124804
Access Level:acceso abierto
Palabra clave:Ciencias Exactas
Física
Hadron-Hadron scattering (experiments)
Top physics
Descripción
Sumario:The cross section of a top-quark pair produced in association with a photon is measured in proton-proton collisions at a centre-of-mass energy of √s = 8 TeV with 20.2 fb⁻¹ of data collected by the ATLAS detector at the Large Hadron Collider in 2012. The measurement is performed by selecting events that contain a photon with transverse momentum p<sub>T</sub> > 15 GeV, an isolated lepton with large transverse momentum, large missing transverse momentum, and at least four jets, where at least one is identified as originating from a b-quark. The production cross section is measured in a fiducial region close to the selection requirements. It is found to be 139 ± 7 (stat.) ± 17 (syst.) fb, in good agreement with the theoretical prediction at next-to-leading order of 151 ± 24 fb. In addition, differential cross sections in the fiducial region are measured as a function of the transverse momentum and pseudorapidity of the photon.