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Title: Simultaneous measurements of the tt¯ , W+W- , and Z/γ*ττ production cross-sections in pp collisions at s=7 TeV with the ATLAS detector

Simultaneous measurements of the tt¯, W+W, and Z/γ*→ττ production cross-sections using an integrated luminosity of 4.6 fb–1 of pp collisions at √s=7 TeV collected by the ATLAS detector at the LHC are presented. Events are selected with two high transverse momentum leptons consisting of an oppositely charged electron and muon pair. The three processes are separated using the distributions of the missing transverse momentum of events with zero and greater than zero jet multiplicities. Measurements of the fiducial cross-section are presented along with results that quantify for the first time the underlying correlations in the predicted and measured cross-sections due to proton parton distribution functions. Results indicate that the correlated next-to-leading-order predictions for tt¯ and Z/γ*→ττ underestimate the data, while those at next-to-next-to-leading-order generally describe the data well. The full cross-sections are measured to be σ(tt¯)=181.2 ± 2.8+9.7–9.5 ± 3.3 ± 3.3 pb, σ(W+W) = 53.3 ± 2.7+7.3–8.0 ± 1.0 ± 0.5 pb, and σ(Z/γ*→ττ) = 1174 ± 24+72–87 ± 21 ± 9 pb, where the cited uncertainties are due to statistics, systematic effects, luminosity and the LHC beam energy measurement, respectively. The W+W measurement includes the small contribution from Higgs boson decays, H → W+W.
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Publication Date:
OSTI Identifier:
Grant/Contract Number:
SC00112704; AC03-76SF00515; AC02-06CH11357; AC02-05CH11231
Published Article
Journal Name:
Physical Review. D, Particles, Fields, Gravitation and Cosmology
Additional Journal Information:
Journal Volume: 91; Journal Issue: 5; Journal ID: ISSN 1550-7998
American Physical Society (APS)
Research Org:
Brookhaven National Laboratory (BNL); Argonne National Lab. (ANL), Argonne, IL (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
ATLAS Collaboration
Country of Publication:
United States