학술논문
Measurement of the tt¯tt¯ production cross section in pp collisions at s = 13 TeV with the ATLAS detector
Document Type
article
Author
Aad, G; Abbott, B; Abbott, DC; Abed Abud, A; Abeling, K; Abhayasinghe, DK; Abidi, SH; Abramowicz, H; Abreu, H; Abulaiti, Y; Abusleme Hoffman, AC; Acharya, BS; Achkar, B; Adam, L; Adam Bourdarios, C; Adamczyk, L; Adamek, L; Adelman, J; Adiguzel, A; Adorni, S; Adye, T; Affolder, AA; Afik, Y; Agapopoulou, C; Agaras, MN; Agarwala, J; Aggarwal, A; Agheorghiesei, C; Aguilar-Saavedra, JA; Ahmad, A; Ahmadov, F; Ahmed, WS; Ai, X; Aielli, G; Akatsuka, S; Akbiyik, M; Åkesson, TPA; Akimov, AV; Al Khoury, K; Alberghi, GL; Albert, J; Alconada Verzini, MJ; Alderweireldt, S; Aleksa, M; Aleksandrov, IN; Alexa, C; Alexopoulos, T; Alfonsi, A; Alfonsi, F; Alhroob, M; Ali, B; Ali, S; Aliev, M; Alimonti, G; Allaire, C; Allbrooke, BMM; Allport, PP; Aloisio, A; Alonso, F; Alpigiani, C; Alunno Camelia, E; Alvarez Estevez, M; Alviggi, MG; Amaral Coutinho, Y; Ambler, A; Ambroz, L; Amelung, C; Amidei, D; Amor Dos Santos, SP; Amoroso, S; Amrouche, CS; Anastopoulos, C; Andari, N; Andeen, T; Anders, JK; Andrean, SY; Andreazza, A; Andrei, V; Angelidakis, S; Angerami, A; Anisenkov, AV; Annovi, A; Antel, C; Anthony, MT; Antipov, E; Antonelli, M; Antrim, DJA; Anulli, F; Aoki, M; Aparisi Pozo, JA; Aparo, MA; Aperio Bella, L; Aranzabal, N; Araujo Ferraz, V; Arcangeletti, C; Arce, ATH; Arena, E; Arguin, J-F; Argyropoulos, S; Arling, J-H
Source
Journal of High Energy Physics. 2021(11)
Subject
Language
Abstract
A measurement of four-top-quark production using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the Large Hadron Collider corresponding to an integrated luminosity of 139 fb−1 is presented. Events are selected if they contain a single lepton (electron or muon) or an opposite-sign lepton pair, in association with multiple jets. The events are categorised according to the number of jets and how likely these are to contain b-hadrons. A multivariate technique is then used to discriminate between signal and background events. The measured four-top-quark production cross section is found to be 26−15+17 fb, with a corresponding observed (expected) significance of 1.9 (1.0) standard deviations over the background-only hypothesis. The result is combined with the previous measurement performed by the ATLAS Collaboration in the multilepton final state. The combined four-top-quark production cross section is measured to be 24−6+7 fb, with a corresponding observed (expected) signal significance of 4.7 (2.6) standard deviations over the background-only predictions. It is consistent within 2.0 standard deviations with the Standard Model expectation of 12.0 ± 2.4 fb. [Figure not available: see fulltext.].