Measurement of the semileptonic tt-bar gamma production cross section in pp collisions at sqrt(s) = 8 TeV

Abstract

A measurement of the cross section for top quark-antiquark (tt-bar) pairs produced in association with a photon in proton-proton collisions at sqrt(s) = 8 TeV is presented. The analysis uses data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.7 inverse femtobarns. The signal is defined as the production of a tt-bar pair in association with a photon having a transverse energy larger than 25 GeV and an absolute pseudorapidity smaller than 1.44. The measurement is performed in the fiducial phase space corresponding to the semileptonic decay chain of the tt-bar pair, and the cross section is measured relative to the inclusive tt-bar pair production cross section. The fiducial cross section for associated tt-bar pair and photon production is found to be 127 +/- 27 (stat + syst) fb per semileptonic final state. The measured value is in agreement with the theoretical prediction.

arXiv commentReplaced with the published version. Added the journal reference and DOI. All figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/TOP-14-008 (CMS Public Pages)

References in corpus (32)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• The anti-k_t jet clustering algorithm
• FastJet user manual
• A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• Implications of CTEQ global analysis for collider observables
• Single-top Wt-channel production matched with parton showers using the POWHEG method
• Two-loop soft anomalous dimensions for single top quark associated production with a W- or H-
• Description and performance of track and primary-vertex reconstruction with the CMS tracker
• Determination of Jet Energy Calibration and Transverse Momentum Resolution in CMS
• MCFM for the Tevatron and the LHC
• Electroweak gauge boson production at hadron colliders through O(alpha_s^2)
• Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
• Identification of b-quark jets with the CMS experiment
• Performance of electron reconstruction and selection with the CMS detector in proton-proton collisions at sqrt(s) = 8 TeV
• NLO single-top production matched with shower in POWHEG: s- and t-channel contributions
• NNLL resummation for s-channel single top quark production
• Performance of photon reconstruction and identification with the CMS detector in proton-proton collisions at sqrt(s) = 8 TeV
• Measurement of the differential cross section for top quark pair production in pp collisions at sqrt(s) = 8 TeV
• The W boson production cross section at the LHC through O(alpha_s^2)
• Constraining top quark effective theory in the LHC Run II era
• Probing Electroweak Top Quark Couplings at Hadron Colliders
• Measurement of the inelastic proton-proton cross section at sqrt(s) = 7 TeV
• QCD corrections to top quark pair production in association with a photon at hadron colliders
• Measurement of differential cross sections for the production of a pair of isolated photons in pp collisions at sqrt(s) = 7 TeV
• Pinning down electroweak dipole operators of the top quark
• Observation of top-quark pair production in association with a photon and measurement of the $t\bar{t}\gamma$ production cross section in pp collisions at $\sqrt{s}=7$ TeV using the ATLAS detector
• The "Top Priority" at the LHC
• Electromagnetic dipole moments of the top quark
• Precision simulations with TAUOLA and PHOTOS

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