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Abstract:

Abstract: The electroweak production and subsequent decay of single top quarks is determined by the properties of the Wtb vertex. This vertex can be described by the complex parameters of an effective Lagrangian. An analysis of angular distributions of the decay products of single top quarks produced in the t -channel constrains these parameters simultaneously. The analysis described in this paper uses 4.6 fb −1 of proton-proton collision data at (Formula presented.) TeV collected with the ATLAS detector at the LHC. Two parameters are measured simultaneously in this analysis. The fraction f 1 of decays containing transversely polarised W bosons is measured to be 0.37 ± 0.07 (stat.⊕syst.). The phase δ − between amplitudes for transversely and longitudinally polarised W bosons recoiling against left-handed b-quarks is measured to be −0.014π ± 0.036π (stat.⊕syst.). The correlation in the measurement of these parameters is 0.15. These values result in two-dimensional limits at the 95% confidence level on the ratio of the complex coupling parameters g R and V L , yielding Re[g R /V L ] ∈ [−0.36, 0.10] and Im[g R /V L ] ∈ [−0.17, 0.23] with a correlation of 0.11. The results are in good agreement with the predictions of the Standard Model.[Figure not available: see fulltext.] © 2016, The Author(s).

Registro:

Documento: Artículo
Título:Search for anomalous couplings in the W tb vertex from the measurement of double differential angular decay rates of single top quarks produced in the t-channel with the ATLAS detector
Autor:The ATLAS collaboration et al.
Este artículo contiene 2867 autores, consultelos en el artículo en formato pdf.
Filiación: Este artículo contiene 2867 autores con sus filiaciones, consultelas en el artículo en formato pdf.
Palabras clave:Hadron-Hadron scattering
Año:2016
Volumen:2016
Número:4
DOI: http://dx.doi.org/10.1007/JHEP04(2016)023
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_n4_p_TheATLAScollaboration

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Citas:

---------- APA ----------
(2016) . Search for anomalous couplings in the W tb vertex from the measurement of double differential angular decay rates of single top quarks produced in the t-channel with the ATLAS detector. Journal of High Energy Physics, 2016(4).
http://dx.doi.org/10.1007/JHEP04(2016)023
---------- CHICAGO ----------
The ATLAS collaboration. "Search for anomalous couplings in the W tb vertex from the measurement of double differential angular decay rates of single top quarks produced in the t-channel with the ATLAS detector" . Journal of High Energy Physics 2016, no. 4 (2016).
http://dx.doi.org/10.1007/JHEP04(2016)023
---------- MLA ----------
The ATLAS collaboration. "Search for anomalous couplings in the W tb vertex from the measurement of double differential angular decay rates of single top quarks produced in the t-channel with the ATLAS detector" . Journal of High Energy Physics, vol. 2016, no. 4, 2016.
http://dx.doi.org/10.1007/JHEP04(2016)023
---------- VANCOUVER ----------
The ATLAS collaboration. Search for anomalous couplings in the W tb vertex from the measurement of double differential angular decay rates of single top quarks produced in the t-channel with the ATLAS detector. J. High Energy Phys. 2016;2016(4).
http://dx.doi.org/10.1007/JHEP04(2016)023