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Abstract:

This paper presents a measurement of the top quark pair (tt̄) production charge asymmetry AC using 4.7 fb -1 of proton-proton collisions at a centre-of-mass energy √s = 7TeV collected by the ATLAS detector at the LHC. A tt̄-enriched sample of events with a single lepton (electron or muon), missing transverse momentum and at least four high transverse momentum jets, of which at least one is tagged as coming from a b-quark, is selected. A likelihood fit is used to reconstruct the tt̄ event kinematics. A Bayesian unfolding procedure is employed to estimate AC at the parton-level. The measured value of the tt̄ production charge asymmetry is AC = 0.006 ± 0.010, where the uncertainty includes both the statistical and the systematic components. Differential AC measurements as a function of the invariant mass, the rapidity and the transverse momentum of the tt̄- system are also presented. In addition, AC is measured for a subset of events with large tt̄ velocity, where physics beyond the Standard Model could contribute. All measurements are consistent with the Standard Model predictions.

Registro:

Documento: Artículo
Título:Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s = 7 TeV using the ATLAS detector
Autor:Aad, G. et al.
Este artículo contiene 2935 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2935 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Palabras clave:Hadron-Hadron Scattering; Top physics
Año:2014
Volumen:2014
Número:2
DOI: http://dx.doi.org/10.1007/JHEP02(2014)107
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_v2014_n2_p_Aad

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Citas:

---------- APA ----------
(2014) . Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s = 7 TeV using the ATLAS detector. Journal of High Energy Physics, 2014(2).
http://dx.doi.org/10.1007/JHEP02(2014)107
---------- CHICAGO ----------
Aad, G. "Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s = 7 TeV using the ATLAS detector" . Journal of High Energy Physics 2014, no. 2 (2014).
http://dx.doi.org/10.1007/JHEP02(2014)107
---------- MLA ----------
Aad, G. "Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s = 7 TeV using the ATLAS detector" . Journal of High Energy Physics, vol. 2014, no. 2, 2014.
http://dx.doi.org/10.1007/JHEP02(2014)107
---------- VANCOUVER ----------
Aad, G. Measurement of the top quark pair production charge asymmetry in proton-proton collisions at √s = 7 TeV using the ATLAS detector. J. High Energy Phys. 2014;2014(2).
http://dx.doi.org/10.1007/JHEP02(2014)107