Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector

A search is performed for top-quark pairs (tt¯) produced together with a photon (γ) with transverse energy greater than 20 GeV using a sample of tt¯ candidate events in final states with jets, missing transverse momentum, and one isolated electron or muon. The data set used corresponds to an integra...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Alconada Verzini, María Josefina, Alonso, Francisco, Anduaga, Xabier Sebastián, Dova, María Teresa, Monticelli, Fernando Gabriel, Wahlberg, Hernán Pablo, The ATLAS Collaboration
Formato: Articulo
Lenguaje:Inglés
Publicado: 2015
Materias:
Ciencias Exactas
Física
proton-proton collisions
ATLAS detector
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/86781
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-86781
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Exactas
Física
proton-proton collisions
ATLAS detector
spellingShingle Ciencias Exactas
Física
proton-proton collisions
ATLAS detector
Alconada Verzini, María Josefina
Alonso, Francisco
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Wahlberg, Hernán Pablo
The ATLAS Collaboration
Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector
topic_facet Ciencias Exactas
Física
proton-proton collisions
ATLAS detector
description A search is performed for top-quark pairs (tt¯) produced together with a photon (γ) with transverse energy greater than 20 GeV using a sample of tt¯ candidate events in final states with jets, missing transverse momentum, and one isolated electron or muon. The data set used corresponds to an integrated luminosity of 4.59 fb<sup>-1</sup> of proton-proton collisions at a center-of-mass energy of 7 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. In total, 140 and 222 tt¯γ candidate events are observed in the electron and muon channels, to be compared to the expectation of 79±26 and 120±39 non-tt¯γ background events, respectively. The production of tt¯γ events is observed with a significance of 5.3 standard deviations away from the null hypothesis. The tt¯γ production cross section times the branching ratio (BR) of the single-lepton decay channel is measured in a fiducial kinematic region within the ATLAS acceptance. The measured value is σ<sup>fid</sup><sub>tt¯γ</sub>×BR=63±8(stat)<sup>+17</sup><sub>-13</sub>(syst)±1(lumi) fb per lepton flavor, in good agreement with the leading-order theoretical calculation normalized to the next-to-leading-order theoretical prediction of 48±10 fb.
format Articulo
Articulo
author Alconada Verzini, María Josefina
Alonso, Francisco
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Wahlberg, Hernán Pablo
The ATLAS Collaboration
author_facet Alconada Verzini, María Josefina
Alonso, Francisco
Anduaga, Xabier Sebastián
Dova, María Teresa
Monticelli, Fernando Gabriel
Wahlberg, Hernán Pablo
The ATLAS Collaboration
author_sort Alconada Verzini, María Josefina
title Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector
title_short Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector
title_full Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector
title_fullStr Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector
title_full_unstemmed Observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 TeV using the ATLAS detector
title_sort observation of top-quark pair production in association with a photon and measurement of the tt¯γ production cross section in pp collisions at √s = 7 tev using the atlas detector
publishDate 2015
url http://sedici.unlp.edu.ar/handle/10915/86781
work_keys_str_mv AT alconadaverzinimariajosefina observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
AT alonsofrancisco observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
AT anduagaxabiersebastian observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
AT dovamariateresa observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
AT monticellifernandogabriel observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
AT wahlberghernanpablo observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
AT theatlascollaboration observationoftopquarkpairproductioninassociationwithaphotonandmeasurementofthettgproductioncrosssectioninppcollisionsats7tevusingtheatlasdetector
bdutipo_str Repositorios
_version_ 1764820489336782850

Ejemplares similares