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

Date

2017

Authors

Aaboud, M.
Albert, Justin
Chiu, Y. H.
Elliot, Alison A.
Fincke-Keeler, J.
Hamano, Kenji
Hill, Ewan Chin
Keeler, Richard
Kowalewski, Robert
Kuwertz, E. S.

Journal Title

Journal ISSN

Volume Title

Publisher

Journal of High Energy Physics

Abstract

The 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.

Description

Keywords

Exotics, Hadron-Hadron scattering (experiments), vector-like quarks

Citation

Aaboud, 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)052