Measurement of the top quark pair production cross section in PbPb collisions at $$ sqrt{s_{mathrm{NN}}}=5.36 $$ TeV Journal Article uri icon

Overview

abstract

  • ; A; bstract; ; ; The inclusive cross section for top quark pair (; ; ; $$ mathrm{t}overline{mathrm{t}} $$; ; t; ; t; ¯; ; ; ; ; ) production in lead-lead (PbPb) collisions is reported for the first time at a center-of-mass energy per nucleon pair of 5.36 TeV. The analysis uses data corresponding to an integrated luminosity of 1.58 nb; ; −; 1; ; collected by the CMS experiment at the CERN LHC in 2023. The; ; ; $$ mathrm{t}overline{mathrm{t}} $$; ; t; ; t; ¯; ; ; ; ; production cross section,; ; ; $$ {sigma}_{mathrm{t}overline{mathrm{t}}}={3.42}_{-0.51}^{+0.54}{left(mathrm{stat}right)}_{-0.43}^{+0.50}left(mathrm{syst}right) $$; ; ; σ; ; t; ; t; ¯; ; ; ; =; ; 3.42; ; −; 0.51; ; ; +; 0.54; ; ; ; ; stat; ; ; −; 0.43; ; ; +; 0.50; ; ; ; syst; ; ; ; ; μ; b, is measured in dilepton final states using a fit to a multivariate discriminator that combines the decay electron and muon kinematic properties with the multiplicity of bottom quark jets. The result is consistent with perturbative quantum chromodynamics calculations at next-to-next-to-leading order (NNLO) accuracy employing several nuclear parton distribution functions. In addition, the Drell–Yan production cross section (; σ; DY; ) for dilepton masses above 10 GeV and the ratio of; ; ; $$ mathrm{t}overline{mathrm{t}} $$; ; t; ; t; ¯; ; ; ; ; to DY cross sections; ; ; $$ left({R}_{mathrm{t}overline{mathrm{t}}/mathrm{DY}}right) $$; ; ; ; R; ; t; ; t; ¯; ; /; DY; ; ; ; ; ; ; are found to be compatible with the NNLO predictions. The observables; ; ; $$ {sigma}_{mathrm{t}overline{mathrm{t}}} $$; ; ; σ; ; t; ; t; ¯; ; ; ; ; ; ; ,; σ; DY; , and; ; ; $$ {R}_{mathrm{t}overline{mathrm{t}}/mathrm{DY}} $$; ; ; R; ; t; ; t; ¯; ; /; DY; ; ; ; ; ; are measured separately for central and semicentral PbPb collisions to investigate for the first time the dependence of top quark production on the collision impact parameter.;

publication date

  • August 6, 2026

Date in CU Experts

  • September 2, 2026 5:03 AM

Full Author List

  • Belyaev A; Gevorgyan A; Hayrapetyan A; Tumasyan A; Adam W; Benato L; Bergauer T; Dragicevic M; Hussain PS; Jeitler M

author count

  • 2528

Other Profiles

Electronic International Standard Serial Number (EISSN)

  • 1029-8479

Additional Document Info

volume

  • 2026

issue

  • 8

number

  • 54