Observation of four-top-quark production in the multilepton final state with the ATLAS detector

0576671 - FZÚ 2024 RIV DE eng J - Journal Article
Aad, G. - Abbott, B. - Abeling, K. - Chudoba, Jiří - Federičová, Pavla - Hejbal, Jiří - Jačka, Petr - Kepka, Oldřich - Kroll, Jiří - Kupčo, Alexander - Latoňová, Věra - Lokajíček, Miloš - Lysák, Roman - Marčišovský, Michal - Mikeštíková, Marcela - Němeček, Stanislav - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek … Total 2978 authors
Observation of four-top-quark production in the multilepton final state with the ATLAS detector.
European Physical Journal C. Roč. 83, č. 6 (2023), č. článku 496. ISSN 1434-6044. E-ISSN 1434-6052
Research Infrastructure: CERN-CZ III - 90240
Institutional support: RVO:68378271
Keywords : Higgs particle: coupling * coupling: Yukawa * background * final state: ((n)jet dilepton)
OECD category: Particles and field physics
Impact factor: 4.4, year: 2022
Method of publishing: Open access

This paper presents the observation of four-top-quark (ttˉttˉttˉttˉ) production in proton-proton collisions at the LHC. The analysis is performed using an integrated luminosity of 140 fb−1fb−1 at a centre-of-mass energy of 13 TeV collected using the ATLAS detector. Events containing two leptons with the same electric charge or at least three leptons (electrons or muons) are selected. Event kinematics are used to separate signal from background through a multivariate discriminant, and dedicated control regions are used to constrain the dominant backgrounds. The observed (expected) significance of the measured ttˉttˉttˉttˉ signal with respect to the standard model (SM) background-only hypothesis is 6.1 (4.3) standard deviations. The ttˉttˉttˉttˉ production cross section is measured to be 22.5−5.5+6.622.5−5.5+6.6​ fb, consistent with the SM prediction of 12.0±2.412.0±2.4 fb within 1.8 standard deviations.
Permanent Link: https://hdl.handle.net/11104/0346122