Search for pair production of vector-like top quarks in events with one lepton, jets, and missing transverse momentum in $\sqrt{s}=13$ TeV pp collisions with the ATLAS detector

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 $Z(\to \nu \nu )t+X$ decay channel. LHC pp collision data at a centre-of-mass energy of $\sqrt{s}=13$ TeV recorded by the ATLAS detector in 2015 and 2016 are used, corresponding to an integrated luminosity of 36.1 ${\mathrm{fb}}^{-1}$. 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.

39 pages in total, author list starting page 23, 7 figures, 5 tables, submitted to JHEP, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2016-15/

References in corpus (10)

• PYTHIA 6.4 Physics and Manual
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• New parton distributions for collider physics
• Event generation with SHERPA 1.1
• Herwig++ Physics and Manual
• Vector boson production at hadron colliders: a fully exclusive QCD calculation at NNLO
• Single-top Wt-channel production matched with parton showers using the POWHEG method
• Two-loop soft anomalous dimensions for single top quark associated production with a W- or H-
• Luminosity determination in pp collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector at the LHC
• HistFitter software framework for statistical data analysis

Cited by in corpus (50)

• From the trees to the forest: a review of radiative neutrino mass models
• Jet Substructure at the Large Hadron Collider: Experimental Review
• Combination of the searches for pair-produced vector-like partners of the third-generation quarks at $\sqrt{s}=$ 13 TeV with the ATLAS detector
• MatchingTools: a Python library for symbolic effective field theory calculations
• Search for vector-like T and B quark pairs in final states with leptons at $\sqrt{s}=$ 13 TeV
• Search for pair production of up-type vector-like quarks and for four-top-quark events in final states with multiple $b$-jets with the ATLAS detector
• Prospects for vectorlike leptons at future proton-proton colliders
• Search for single production of a vector-like T quark decaying to a Z boson and a top quark in proton-proton collisions at $\sqrt{s}=$13 TeV
• The experimental status of direct searches for exotic physics beyond the standard model at the Large Hadron Collider
• Flavor anomalies and dark matter in SUSY with an extra U(1)
• Vector-like Singlet Quarks: a Roadmap
• Search for pair production of heavy vector-like quarks decaying into hadronic final states in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for vector-like quarks in events with two oppositely charged leptons and jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Exotic decays of top partners: mind the search gap
• Search for single production of vector-like quarks decaying into $Wb$ in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for single production of vector-like quarks decaying to a top quark and a W boson in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Single production of vector-like quarks with large width at the Large Hadron Collider
• Search for pair production of vector-like T and B quarks in single-lepton final states using boosted jet substructure in proton-proton collisions at sqrt(s) = 13 TeV
• Transferability of Deep Learning Models in Searches for New Physics at Colliders
• New sensitivity of current LHC measurements to vector-like quarks
• QCD Baryogenesis
• Search for electroweak production of a vector-like T quark using fully hadronic final states
• Search for single production of a vector-like $T$ quark decaying into a Higgs boson and top quark with fully hadronic final states using the ATLAS detector
• Novel Interpretation Strategy for Searches of Singly Produced Vector-like Quarks at the LHC
• Search for large missing transverse momentum in association with one top-quark in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Exotic Vector-Like Quark Phenomenology in the Minimal Linear $\sigma$ Model
• Search for pair-produced vector-like top and bottom partners in events with large missing transverse momentum in pp collisions with the ATLAS detector
• Exotic Signals of Vectorlike Quarks
• Search for single production of a vector-like T quark decaying to a top quark and a Z boson in the final state with jets and missing transverse momentum at $\sqrt{s}=$ 13 TeV
• Heavy quark-philic scalar dark matter with a vector-like fermion portal
• Phenomenology of unusual top partners in composite Higgs models
• Hunting for top partner with a new signature at the LHC
• $B$ decay anomalies from nonabelian local horizontal symmetry
• The $W\gamma$ decay of the elusive charged Higgs boson in the two-Higgs-doublet model with vectorlike fermions
• Disentangling new physics effects on non-resonant Higgs boson pair production from gluon fusion
• Vector-like quarks: status and new directions at the LHC
• Probing Charged Higgs Bosons in the 2-Higgs Doublet Model Type-II with Vector-Like Quarks
• Vacuum stability in the Standard Model with vector-like fermions
• Search for a heavy resonance decaying to a top quark and a vector-like top quark in the lepton+jets final state in pp collisions at $\sqrt{s}=$ 13 TeV
• Neutral-naturalness from a holographic SO(6)/SO(5) composite Higgs model
• Search for singly produced vector-like top partners in multilepton final states with 139 ${\mathrm{fb}}^{-1}$ of $pp$ collision data at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for single production of vectorlike $B$-quarks at the LHC
• Pseudoscalar decays to gauge bosons at the LHC and at a future 100 TeV collider
• Modelling top partner-vector resonance phenomenology
• Long-lived Searches of Vector-like Lepton and Its Accompanying Scalar at Colliders
• Composite Higgs at high transverse momentum
• Down type iso-singlet quarks at the HL-LHC and FCC-hh
• Combination of searches for singly produced vector-like top quarks in pp collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Vector-Like top quark production via a chromo-magnetic moment at the LHC
• Phenomenology of extra quarks at the LHC