0619727 - FZÚ 2026 RIV US eng J - Journal Article
Aad, G. - Aakvaag, E. - Abbott, B. - Chudoba, Jiří - Federičová, Pavla - Hejbal, Jiří - Jačka, Petr - Kepka, Oldřich - Kroll, Jiří - Kupčo, Alexander - Latoňová, Věra - Lysák, Roman - Marčišovský, Michal - Mikeštíková, Marcela - Nechanský, Filip - Němeček, Stanislav - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek … Total 2885 authors
Observation of t¯t production in Pb+Pb collisions at √s_NN = 5.02 TeV with the ATLAS detector.
Physical Review Letters. Roč. 134, č. 14 (2025), č. článku 142301. ISSN 0031-9007. E-ISSN 1079-7114
R&D Projects: GA MŠMT(CZ) EH22_008/0004632
Research Infrastructure: CERN-CZ III - 90240
Institutional support: RVO:68378271
Keywords : LHC * ATLAS * CERN * top-quark
OECD category: Particles and field physics
Impact factor: 8.1, year: 2023 ; AIS: 3.013, rok: 2023
Method of publishing: Open access
DOI: https://doi.org/10.1103/PhysRevLett.134.142301

Top-quark pair production is observed in lead–lead (Pb+Pb) collisions at sNN=5.02  TeV at the Large Hadron Collider with the ATLAS detector. The data sample was recorded in 2015 and 2018, amounting to an integrated luminosity of 1.9  nb-1. Events with exactly one electron and one muon and at least two jets are selected. Top-quark pair production is measured with an observed (expected) significance of 5.0 (4.1) standard deviations. The measured top-quark pair production cross section is σtt¯=3.6 -0.9+1.0(stat) -0.5+0.8(syst)  μb, with a total relative uncertainty of 31%, and is consistent with theoretical predictions using a range of different nuclear parton distribution functions. The observation of this process consolidates the evidence of the existence of all quark flavors in the preequilibrium stage of the quark-gluon plasma at very high energy densities, similar to the conditions present in the early Universe.
Permanent Link: https://hdl.handle.net/11104/0366371