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Abstract:

Measurements of top quark spin observables in tt¯ events are presented based on 20.2 fb −1 of s=8 TeV proton-proton collisions recorded with the ATLAS detector at the LHC. The analysis is performed in the dilepton final state, characterised by the presence of two isolated leptons (electrons or muons). There are 15 observables, each sensitive to a different coefficient of the spin density matrix of tt¯ production, which are measured independently. Ten of these observables are measured for the first time. All of them are corrected for detector resolution and acceptance effects back to the parton and stable-particle levels. The measured values of the observables at parton level are compared to Standard Model predictions at next-to-leading order in QCD. The corrected distributions at stable-particle level are presented and the means of the distributions are compared to Monte Carlo predictions. No significant deviation from the Standard Model is observed for any observable.[Figure not available: see fulltext.] © 2017, The Author(s).

Registro:

Documento: Artículo
Título:Measurements of top quark spin observables in tt¯ events using dilepton final states in √s=8 TeV pp collisions with the ATLAS detector
Autor:The ATLAS collaboration et al.
Este artículo contiene 2852 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2852 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Palabras clave:Hadron-Hadron scattering (experiments)
Año:2017
Volumen:2017
Número:3
DOI: http://dx.doi.org/10.1007/JHEP03(2017)113
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_v2017_n3_p_TheATLAScollaboration

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Citas:

---------- APA ----------
(2017) . Measurements of top quark spin observables in tt¯ events using dilepton final states in √s=8 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics, 2017(3).
http://dx.doi.org/10.1007/JHEP03(2017)113
---------- CHICAGO ----------
The ATLAS collaboration. "Measurements of top quark spin observables in tt¯ events using dilepton final states in √s=8 TeV pp collisions with the ATLAS detector" . Journal of High Energy Physics 2017, no. 3 (2017).
http://dx.doi.org/10.1007/JHEP03(2017)113
---------- MLA ----------
The ATLAS collaboration. "Measurements of top quark spin observables in tt¯ events using dilepton final states in √s=8 TeV pp collisions with the ATLAS detector" . Journal of High Energy Physics, vol. 2017, no. 3, 2017.
http://dx.doi.org/10.1007/JHEP03(2017)113
---------- VANCOUVER ----------
The ATLAS collaboration. Measurements of top quark spin observables in tt¯ events using dilepton final states in √s=8 TeV pp collisions with the ATLAS detector. J. High Energy Phys. 2017;2017(3).
http://dx.doi.org/10.1007/JHEP03(2017)113