Search for pair production of vector-like top quarks in events with one lepton, jets, and missing transverse momentum in root S=13 TeV pp collisions with the ATLAS detector

Adersberger, M.; Bender, M.; Biebel, O.; Bock, C.; Bogavac, D.; Duckeck, G.; Flierl, B. M.; Hartmann, N. M.; Heinrich, J. J.; Hertenberger, R.; Hönig, F.; Legger, F.; Lorenz, J.; Lösel, P. J.; Maier, T.; Mann, A.; Mehlhase, S.; Mitrevski, J.; Müller, R. S. P.; Schachtner, B. M.; Rauscher, F.; Schaile, D.; Unverdorben, C.; Valderanis, C.; Wagner-Kuhr, J. und Walker, R. (2017): Search for pair production of vector-like top quarks in events with one lepton, jets, and missing transverse momentum in root S=13 TeV pp collisions with the ATLAS detector. In: Journal of High Energy Physics, Nr. 8: S. 1-40

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(->nu nu) t + X decay channel. LHC pp collision data at a centre-of-mass energy of root S = 13TeV 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.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 1029-8479
• Bemerkung: SCOAP3-Publikation. - Weitere Autoren siehe PDF-Volltext
• Sprache: Englisch