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dc.contributor.authorAad, G.en_US
dc.contributor.authorAbbott, B.en_US
dc.contributor.authorAbdallah, J.en_US
dc.contributor.authorAbdel Khalek, S.en_US
dc.contributor.authorAbdinov, O.en_US
dc.contributor.authorAben, R.en_US
dc.contributor.authorAbi, B.en_US
dc.contributor.authorIzen, Joseph M.en_US
dc.contributor.authorLeyton, Michaelen_US
dc.contributor.authorLou, Xinchouen_US
dc.contributor.authorNamasivayam, Harisankaren_US
dc.contributor.authorReeves, Kendallen_US
dc.contributor.authorATLAS Collaborationen_US
dc.date.accessioned2015-02-04T17:51:26Z
dc.date.available2015-02-04T17:51:26Z
dc.date.created2014-10-29en_US
dc.date.issued2014-10-29en_US
dc.identifier.issn1434-6044en_US
dc.identifier.urihttp://hdl.handle.net/10735.1/4302
dc.description.abstractThe inclusive top quark pair (tt̅) production cross-section σ_{tt̅} has been measured in proton–proton collisions at √s = 7 TeV and √s = 8 TeV with the ATLAS experiment at the LHC, using tt̅ events with an opposite charge eμ pair in the final state. The measurement was performed with the 2011 7 TeV dataset corresponding to an integrated luminosity of 4.6 fb⁻¹ and the 2012 8 TeV dataset of 20.3 fb⁻¹. The numbers of events with exactly one and exactly two b-tagged jets were counted and used to simultaneously determine σ_{tt̅} and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section was measured to be: σ_{tt̅} =182.9 ± 3.1 ± 4.2 ± 3.6 ± 3.3 pb (s√ = 7 TeV) and σ_{tt̅} = 242.4 ± 1.7 ± 5.5 ± 7.5 ± 4.2 pb (s√ = 8 TeV), where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, knowledge of the integrated luminosity and of the LHC beam energy. The results are consistent with recent theoretical QCD calculations at next-to-next-to-leading order. Fiducial measurements corresponding to the experimental acceptance of the leptons are also reported, together with the ratio of cross-sections measured at the two centre-of-mass energies. The inclusive cross-section results were used to determine the top quark pole mass via the dependence of the theoretically predicted cross-section on m_{t^{pole}} = giving a result of m_{t^{pole}}172.9{{_-2.6)^{+2.5}} GeV. By looking for an excess of tt̅ production with respect to the QCD prediction, the results were also used to place limits on the pair-production of supersymmetric top squarks t˜₁ with masses close to the top quark mass, decaying via t˜₁ → tχ˜{₁⁻⁰} to predominantly right-handed top quarks and a light neutralino χ˜{₁⁰}, the lightest supersymmetric particle. Top squarks with masses between the top quark mass and 177 GeV are excluded at the 95% confidence level.en_US
dc.language.isoen_USen_US
dc.publisherSpringer New York LLCen_US
dc.relation.urihttp://dx.doi.org/10.1140/epjc/s10052-014-3109-7
dc.rightsCC BY 4.0 (Attribution)en_US
dc.rights©2014 The Authorsen_US
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/en_US
dc.sourceEuropean Physical Journal C
dc.subjectTop Quarksen_US
dc.subjectJets (Nuclear physics)en_US
dc.subjectLeptonsen_US
dc.subjectElectronsen_US
dc.subjectBosonsen_US
dc.titleMeasurement of the tt̅ Production Cross-Section Using eμ Events with b-Tagged Jets in pp Collisions at √s = 7 and 8 TeV with the ATLAS Detectoren_US
dc.typeTexten_US
dc.type.genreArticleen_US
dc.identifier.bibliographicCitationAad, G., B. Abbott, J. Abdallah, S. Abdel Khalek, et al. 2014. "Measurement of the tt̅ production cross-section using eμ events with b-tagged jets in pp collisions at √s = 7 and 8 TeV with the ATLAS Detector" European Physical Journal C 74(10): 1-32.en_US
dc.identifier.volume74en_US
dc.identifier.issue3109en_US
dc.contributor.utdAuthorIzen, Joseph M.en_US
dc.contributor.utdAuthorLeyton, Michaelen_US
dc.contributor.utdAuthorNamasivayam, Harisankaren_US
dc.contributor.utdAuthorReeves, Kendallen_US
dc.contributor.utdAuthorLou, Xinchouen_US
dc.contributor.VIAF250674117 (Izen, JM)en_US
dc.contributor.VIAF250674117 (Izen, JM)
dc.contributor.ORCID0000-0003-0867-2189 (Lou, X)


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