Measurement of the top-quark mass in tt¯ + 1-jet events collected with the ATLAS detector in pp collisions at √s = 8 TeV

A determination of the top-quark mass is presented using 20.2 fb⁻¹ of 8 TeV proton-proton collision data produced by the Large Hadron Collider and collected by the ATLAS experiment. The normalised differential cross section of top-quark pair production in association with an energetic jet is measure...

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Detalles Bibliográficos
Autores: Alonso, Francisco, Arduh, Francisco Anuar, Dova, María Teresa, Hoya, Joaquín, Monticelli, Fernando Gabriel, Orellana, Gonzalo Enrique, Wahlberg, Hernán Pablo, The ATLAS Collaboration
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/124610
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/124610
Access Level:acceso abierto
Palabra clave:Ciencias Exactas
Física
Hadron-Hadron scattering (experiments)
Top physics
Descripción
Sumario:A determination of the top-quark mass is presented using 20.2 fb⁻¹ of 8 TeV proton-proton collision data produced by the Large Hadron Collider and collected by the ATLAS experiment. The normalised differential cross section of top-quark pair production in association with an energetic jet is measured in the lepton+jets final state and unfolded to parton and particle levels. The unfolded distribution at parton level can be described using next-to-leading-order QCD predictions in terms of either the top-quark pole mass or the running mass as defined in the (modified) minimal subtraction scheme. A comparison between the experimental distribution and the theoretical prediction allows the top-quark mass to be extracted in the two schemes. The value obtained for the pole-mass scheme is: m<sup>pole</sup><sub>t</sub> = 171.1 ± 0.4 (stat) ± 0.9 (syst) <sup>+0.7</sup> <sub>−0.3</sub> (theo) GeV. The extracted value in the running-mass scheme is: m<sub>t</sub>(m<sub>t</sub>) = 162.9 ± 0.5 (stat) ± 1.0 (syst) <sup>+2.1</sup> <sub>−1.2</sub> (theo) GeV. The results for the top-quark mass using the two schemes are consistent, when translated from one scheme to the other.