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Abstract:

This Letter presents evidence for single top-quark production in the s-channel using proton–proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS detector at the CERN Large Hadron Collider. The analysis is performed on events containing one isolated electron or muon, large missing transverse momentum and exactly two b-tagged jets in the final state. The analysed data set corresponds to an integrated luminosity of 20.3 fb −1 . The signal is extracted using a maximum-likelihood fit of a discriminant which is based on the matrix element method and optimized in order to separate single-top-quark s-channel events from the main background contributions, which are top-quark pair production and W boson production in association with heavy-flavour jets. The measurement leads to an observed signal significance of 3.2 standard deviations and a measured cross-section of σ s =4.8±0.8(stat.) −1.3 +1.6 (syst.) pb, which is consistent with the Standard Model expectation. The expected significance for the analysis is 3.9 standard deviations. © 2016 CERN for the benefit of the ATLAS Collaboration

Registro:

Documento: Artículo
Título:Evidence for single top-quark production in the s-channel in proton–proton collisions at √s=8 TeV with the ATLAS detector using the Matrix Element Method
Autor:Aad, G. et al.
Este artículo contiene 2873 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2873 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Año:2016
Volumen:756
Página de inicio:228
Página de fin:246
DOI: http://dx.doi.org/10.1016/j.physletb.2016.03.017
Título revista:Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
Título revista abreviado:Phys Lett Sect B Nucl Elem Part High-Energy Phys
ISSN:03702693
CODEN:PYLBA
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_03702693_v756_n_p228_Aad

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Citas:

---------- APA ----------
(2016) . Evidence for single top-quark production in the s-channel in proton–proton collisions at √s=8 TeV with the ATLAS detector using the Matrix Element Method. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 756, 228-246.
http://dx.doi.org/10.1016/j.physletb.2016.03.017
---------- CHICAGO ----------
Aad, G. "Evidence for single top-quark production in the s-channel in proton–proton collisions at √s=8 TeV with the ATLAS detector using the Matrix Element Method" . Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 756 (2016) : 228-246.
http://dx.doi.org/10.1016/j.physletb.2016.03.017
---------- MLA ----------
Aad, G. "Evidence for single top-quark production in the s-channel in proton–proton collisions at √s=8 TeV with the ATLAS detector using the Matrix Element Method" . Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol. 756, 2016, pp. 228-246.
http://dx.doi.org/10.1016/j.physletb.2016.03.017
---------- VANCOUVER ----------
Aad, G. Evidence for single top-quark production in the s-channel in proton–proton collisions at √s=8 TeV with the ATLAS detector using the Matrix Element Method. Phys Lett Sect B Nucl Elem Part High-Energy Phys. 2016;756:228-246.
http://dx.doi.org/10.1016/j.physletb.2016.03.017