Aaboud, M.Albert, JustinChiu, Y. H.Elliot, Alison A.Fincke-Keeler, J.Hamano, KenjiHill, Ewan ChinKeeler, RichardKowalewski, RobertKuwertz, E. S.Kwan, TonyLeBlanc, Matthew EdgarLefebvre, MichelMcPherson, Robert A.Seuster, RolfSobie, Randall J.Trovatelli, M.Venturi, M.ATLAS Collaboration2020-03-092020-03-0920172017Aaboud, M.; Aad, G.; Abbott, B.; Abdinov, O.; Abeloos, B.; Abidi, S. H.; … & Zwalinski, L. (2017). Search for pair production of vector-like top quarks in events with one lepton, jets, and missing transverse momentum in √s=13 TeV pp collisions with the ATLAS detector. Journal of High Energy Physics, 2017(8), article 52. DOI: 10.1007/JHEP08(2017)052https://doi.org/10.1007/JHEP08(2017)052http://hdl.handle.net/1828/11621The results of a search for vector-like top quarks using events with exactly one lepton, at least four jets, and large missing transverse momentum are reported. The search is optimised for pair production of vector-like top quarks in the Z(→νν) t + X decay channel. LHC pp collision data at a centre-of-mass energy of s√=13 TeV recorded by the ATLAS detector in 2015 and 2016 are used, corresponding to an integrated luminosity of 36.1 fb−1. No significant excess over the Standard Model expectation is seen and upper limits on the production cross-section of a vector-like T quark pair as a function of the T quark mass are derived. The observed (expected) 95% CL lower limits on the T mass are 870 GeV (890 GeV) for the weak-isospin singlet model, 1.05 TeV (1.06 TeV) for the weak-isospin doublet model and 1.16 TeV (1.17 TeV) for the pure Zt decay mode. Limits are also set on the mass as a function of the decay branching ratios, excluding large parts of the parameter space for masses below 1 TeV.enExoticsHadron-Hadron scattering (experiments)vector-like quarksArticle