Combination of inclusive top-quark pair production cross-section measurements using ATLAS and CMS data at s = 7 and 8 TeV


Aad G., Abbott B., Abbott D., Abed Abud A., Abeling K., Abhayasinghe D., ...More

Journal of High Energy Physics, vol.2023, no.7, 2023 (SCI-Expanded, Scopus) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 2023 Issue: 7
  • Publication Date: 2023
  • Doi Number: 10.1007/jhep07(2023)213
  • Journal Name: Journal of High Energy Physics
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, INSPEC, zbMATH, Directory of Open Access Journals, Nature Index
  • Keywords: Hadron-Hadron Scattering, Top Physics
  • Yıldız Technical University Affiliated: No

Abstract

A combination of measurements of the inclusive top-quark pair production cross-section performed by ATLAS and CMS in proton–proton collisions at centre-of-mass energies of 7 and 8 TeV at the LHC is presented. The cross-sections are obtained using top-quark pair decays with an opposite-charge electron–muon pair in the final state and with data corresponding to an integrated luminosity of about 5 fb−1 at s = 7 TeV and about 20 fb−1 at s = 8 TeV for each experiment. The combined cross-sections are determined to be 178.5 ± 4.7 pb at s = 7 TeV and 243.3−5.9+6.0 pb at s = 8 TeV with a correlation of 0.41, using a reference top-quark mass value of 172.5 GeV. The ratio of the combined cross-sections is determined to be R8/7 = 1.363 ± 0.032. The combined measured cross-sections and their ratio agree well with theory calculations using several parton distribution function (PDF) sets. The values of the top-quark pole mass (with the strong coupling fixed at 0.118) and the strong coupling (with the top-quark pole mass fixed at 172.5 GeV) are extracted from the combined results by fitting a next-to-next-to-leading-order plus next-to-next-to-leading-log QCD prediction to the measurements. Using a version of the NNPDF3.1 PDF set containing no top-quark measurements, the results obtained are mtpole=173.4−2.0+1.8 GeV and αsmZ=0.1170−0.0018+0.0021.