@misc{10481/60162,
year = {2019},
month = {3},
url = {http://hdl.handle.net/10481/60162},
abstract = {A search for four-top-quark production, tt¯tt¯, is presented. It is based on proton-proton collision data with a center-of-mass energy s√ = 13 TeV collected by the ATLAS detector at the Large Hadron Collider during the year 2015 and 2016, corresponding to an integrated luminosity of 36.1 fb−1. Data are analyzed in both the single-lepton and opposite-sign dilepton channels, characterized by the presence of one or two isolated electrons or muons with high-transverse momentum and multiple jets. A data-driven method is used to estimate the dominant background from top-quark pair production in association with jets. No significant excess above the Standard Model expectation is observed. The result is combined with the previous same-sign dilepton and multilepton searches carried out by ATLAS and an observed (expected) upper limit of 5.3 (2.1) times the four-top-quark Standard Model cross section is obtained at 95% confidence level. Additionally, upper limit on anomalous four-top-quark production cross section is set in the context of an effective field theory model.},
organization = {We acknowledge the support of ANPCyT, Argentina;
YerPhI, Armenia; ARC, Australia; BMWFW and FWF,
Austria; ANAS, Azerbaijan; SSTC, Belarus; CNPq and
FAPESP, Brazil; NSERC, NRC and CFI, Canada; CERN;
CONICYT, Chile; CAS, MOST and NSFC, China; COLCIENCIAS, Colombia; MSMT CR, MPO CR and
VSC CR, Czech Republic; DNRF and DNSRC,
Denmark; IN2P3-CNRS, CEA-DRF/IRFU, France;
SRNSFG, Georgia; BMBF, HGF, and MPG, Germany;
GSRT, Greece; RGC, Hong Kong SAR, China; ISF and
Benoziyo Center, Israel; INFN, Italy; MEXT and JSPS,
Japan; CNRST, Morocco; NWO, Netherlands; RCN,
Norway; MNiSW and NCN, Poland; FCT, Portugal;
MNE/IFA, Romania; MES of Russia and NRC KI,
Russian Federation; JINR; MESTD, Serbia; MSSR,
Slovakia; ARRS and MIZŠ, Slovenia; DST/NRF, South
Africa; MINECO, Spain; SRC and Wallenberg
Foundation, Sweden; SERI, SNSF and Cantons of
Bern and Geneva, Switzerland; MOST, Taiwan; TAEK,
Turkey; STFC, United Kingdom; DOE and NSF, United
States of America. In addition, individual groups and
members have received support from BCKDF,
CANARIE, CRC and Compute Canada, Canada;
COST, ERC, ERDF, Horizon 2020, and Marie
Skłodowska-Curie Actions, European Union;
Investissements d’ Avenir Labex and Idex, ANR,
France; DFG and AvH Foundation, Germany;
Herakleitos, Thales and Aristeia programmes co-financed
by EU-ESF and the Greek NSRF, Greece; BSF-NSF and
GIF, Israel; CERCA Programme Generalitat de
Catalunya, Spain; The Royal Society and Leverhulme
Trust, United Kingdom.},
publisher = {American Physical Society},
title = {Search for four-top-quark production in the single-lepton and opposite-sign dilepton final states in pp collisions at √s = 13 TeV with the ATLAS detector},
doi = {10.1103/PhysRevD.99.052009},
author = {Aaboud, M. and Aguilar Saavedra, Juan Antonio and Atlas Collaboration},
}