Measurement of associated production of vector bosons and top quark-antiquark pairs at sqrt(s) = 7 TeV

Abstract

The first measurement of vector-boson production associated with a top quark-antiquark pair in proton-proton collisions at sqrt(s) = 7 TeV is presented. The results are based on a data set corresponding to an integrated luminosity of 5.0 inverse femtobarms, recorded by the CMS detector at the LHC in 2011. The measurement is performed in two independent channels through a trilepton analysis of t t-bar Z events and a same-sign dilepton analysis of t t-bar V (V = W or Z) events. In the trilepton channel a direct measurement of the t t-bar Z cross section sigma(t t-bar Z) = 0.28 +0.14/-0.11 (stat) +0.06/-0.03 (syst) pb is obtained. In the dilepton channel a measurement of the t t-bar V cross section yields sigma(t t-bar V) = 0.43 +0.17/-0.15 (stat) +0.09/-0.07 (syst) pb. These measurements have a significance, respectively, of 3.3 and 3.0 standard deviations from the background hypotheses and are compatible, within uncertainties, with the corresponding next-to-leading order predictions of 0.137 +0.012/-0.016 and 0.306 +0.031/-0.053 pb.

Replaced with published version. Added journal reference and DOI

References in corpus (8)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• PYTHIA 6.4 Physics and Manual
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• The Catchment Area of Jets
• Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
• t tbar W and t tbar Z Hadroproduction at NLO accuracy in QCD with Parton Shower and Hadronization effects
• Search for new physics with same-sign isolated dilepton events with jets and missing transverse energy

Cited by in corpus (30)

• Evidence for the 125 GeV Higgs boson decaying to a pair of tau leptons
• Search for the associated production of the Higgs boson with a top-quark pair
• Measurement of the cross section for top quark pair production in association with a W or Z boson in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Associated production of a top quark pair with a heavy electroweak gauge boson at NLO+NNLL accuracy
• Search for top-squark pairs decaying into Higgs or Z bosons in pp collisions at sqrt(s) = 8 TeV
• Top-quark charge asymmetry and polarization in $t\bar{t}{W}^{\pm }$ production at the LHC
• Associated top quark pair production with a heavy boson: differential cross sections at NLO+NNLL accuracy
• Constraining couplings of the top quarks to the Z boson in ttbar+Z production at the LHC
• Measurement of top quark-antiquark pair production in association with a W or Z boson in pp collisions at sqrt(s) = 8 TeV
• Observation of top quark pairs produced in association with a vector boson in pp collisions at sqrt(s) = 8 TeV
• Measurement of the $t\bar{t}W$ and $t\bar{t}Z$ production cross sections in $pp$ collisions at $\sqrt{s}=8\mathrm{Te}\mathrm{V}$ with the ATLAS detector
• Electroweak and QCD corrections to top-pair hadroproduction in association with heavy bosons
• Probing anomalous $t\bar{t}Z$ interactions with rare meson decays
• A precise determination of top quark electro-weak couplings at the ILC operating at $\roots=500\,\GeV$
• Renormalization group improved predictions for $t\bar{t}{W}^{\pm }$ production at hadron colliders
• Top-quark physics at the Large Hadron Collider
• The Top Quark
• Search for pair production of excited top quarks in the lepton + jets final state
• Triple top quark production in Standard Model
• Top quark precision physics at the International Linear Collider
• A precise characterisation of the top quark electro-weak vertices at the ILC
• Dipole-induced anomalous top quark couplings at the LHC
• Properties of the Top Quark
• Top Couplings: pre-Snowmass Energy Frontier 2013 Overview
• Can LHC observe an anomaly in ttZ production?
• Associated production of the $Z$ boson with a pair of top quarks in the left-right twin Higgs model
• Determining Top Quark Couplings at the LHC: Snowmass White Paper
• Top Cross-Sections and Single Top
• Measurements of the top-quark properties at CMS
• Measurement of the $t\bar{t}Z$ Production Cross Section in the Final State with Three Charged Leptons using 36.1 fb${}^{-1}$ of $pp$ Collisions at 13 TeV at the ATLAS Detector