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Abstract:

The cross-section for the production of a single top quark in association with a W boson in proton-proton collisions at √s = 8TeV is measured. The dataset corresponds to an integrated luminosity of 20.3 fb −1 , collected by the ATLAS detector in 2012 at the Large Hadron Collider at CERN. Events containing two leptons and one central b-jet are selected. The W t signal is separated from the backgrounds using boosted decision trees, each of which combines a number of discriminating variables into one classifier. Production of W t events is observed with a significance of 7.7σ. The cross-section is extracted in a profile likelihood fit to the classifier output distributions. The W t cross-section, inclusive of decay modes, is measured to be 23.0 ± 1.3(stat.) − 3.5 + 3.2 (syst.)±1.1(lumi.) pb. The measured cross-section is used to extract a value for the CKM matrix element |V tb | of 1.01 ± 0.10 and a lower limit of 0.80 at the 95% confidence level. The cross-section for the production of a top quark and a W boson is also measured in a fiducial acceptance requiring two leptons with p T > 25 GeV and |η| < 2.5, one jet with p T > 20 GeV and |η| < 2.5, and E T miss > 20 GeV, including both W t and top-quark pair events as signal. The measured value of the fiducial cross-section is 0.85 ± 0.01(stat.) − 0.07 + 0.07 (syst.)±0.03(lumi.) pb. © 2016, The Author(s).

Registro:

Documento: Artículo
Título:Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment
Autor:The ATLAS collaboration et al.
Este artículo contiene 2872 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2872 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Palabras clave:Hadron-Hadron scattering; Top physics
Año:2016
Volumen:2016
Número:1
Página de inicio:1
Página de fin:48
DOI: http://dx.doi.org/10.1007/JHEP01(2016)064
Título revista:Journal of High Energy Physics
Título revista abreviado:J. High Energy Phys.
ISSN:11266708
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_11266708_v2016_n1_p1_TheATLAScollaboration

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Citas:

---------- APA ----------
(2016) . Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment. Journal of High Energy Physics, 2016(1), 1-48.
http://dx.doi.org/10.1007/JHEP01(2016)064
---------- CHICAGO ----------
The ATLAS collaboration. "Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment" . Journal of High Energy Physics 2016, no. 1 (2016) : 1-48.
http://dx.doi.org/10.1007/JHEP01(2016)064
---------- MLA ----------
The ATLAS collaboration. "Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment" . Journal of High Energy Physics, vol. 2016, no. 1, 2016, pp. 1-48.
http://dx.doi.org/10.1007/JHEP01(2016)064
---------- VANCOUVER ----------
The ATLAS collaboration. Measurement of the production cross-section of a single top quark in association with a W boson at 8 TeV with the ATLAS experiment. J. High Energy Phys. 2016;2016(1):1-48.
http://dx.doi.org/10.1007/JHEP01(2016)064