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Abstract:

In the pp→tt¯ process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a measurement of the charge asymmetry in events where the top-quark pair is produced with a large invariant mass. The analysis is performed on 20.3 fb −1 of pp collision data at s=8TeV collected by the ATLAS experiment at the LHC, using reconstruction techniques specifically designed for the decay topology of highly boosted top quarks. The charge asymmetry in a fiducial region with large invariant mass of the top-quark pair (m tt¯ >0.75 TeV) and an absolute rapidity difference of the top and anti-top quark candidates within −2<|y t |−|y t¯ |<2 is measured to be 4.2±3.2%, in agreement with the Standard Model prediction at next-to-leading order. A differential measurement in three tt¯ mass bins is also presented. © 2016 CERN for the benefit of the ATLAS Collaboration

Registro:

Documento: Artículo
Título:Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment
Autor:Aad, G. et al.
Este artículo contiene 2854 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2854 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Año:2016
Volumen:756
Página de inicio:52
Página de fin:71
DOI: http://dx.doi.org/10.1016/j.physletb.2016.02.055
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_p52_Aad

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Citas:

---------- APA ----------
(2016) . Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 756, 52-71.
http://dx.doi.org/10.1016/j.physletb.2016.02.055
---------- CHICAGO ----------
Aad, G. "Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment" . Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 756 (2016) : 52-71.
http://dx.doi.org/10.1016/j.physletb.2016.02.055
---------- MLA ----------
Aad, G. "Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment" . Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol. 756, 2016, pp. 52-71.
http://dx.doi.org/10.1016/j.physletb.2016.02.055
---------- VANCOUVER ----------
Aad, G. Measurement of the charge asymmetry in highly boosted top-quark pair production in √s=8 TeV pp collision data collected by the ATLAS experiment. Phys Lett Sect B Nucl Elem Part High-Energy Phys. 2016;756:52-71.
http://dx.doi.org/10.1016/j.physletb.2016.02.055