Search for pair and single production of vectorlike quarks in final states with at least one $Z$ boson decaying into a pair of electrons or muons in $pp$ collision data collected with the ATLAS detector at $\sqrt{s}=13$ TeV

Abstract

A search for vectorlike quarks is presented, which targets their decay into a $Z$ boson and a third-generation Standard Model quark. In the case of a vectorlike quark $T$ ($B$) with charge $+2/3e$ ($-1/3e$), the decay searched for is $T\to Zt$ ($B\to Zb$). Data for this analysis were taken during 2015 and 2016 with the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 36.1 fb${}^{-1}$ of $pp$ collisions at $\sqrt{s}=13$ TeV. The final state used is characterized by the presence of $b$-tagged jets, as well as a $Z$ boson with high transverse momentum, which is reconstructed from a pair of opposite-sign same-flavor leptons. Pair and single production of vectorlike quarks are both taken into account and are each searched for using optimized dileptonic exclusive and trileptonic inclusive event selections. In these selections, the high scalar sum of jet transverse momenta, the presence of high-transverse-momentum large-radius jets, as well as - in the case of the single-production selections - the presence of forward jets are used. No significant excess over the background-only hypothesis is found and exclusion limits at 95% confidence level allow masses of vectorlike quarks of $m_T>1030$ GeV ($m_T>1210$ GeV) and $m_B>1010$ GeV ($m_B>1140$ GeV) in the singlet (doublet) model. In the case of 100% branching ratio for $T\to Zt$ ($B\to Zb$), the limits are $m_T>1340$ GeV ($m_B>1220$ GeV). Limits at 95% confidence level are also set on the coupling to Standard Model quarks for given vectorlike quark masses.

75 pages in total, author list starting page 59, 17 figures, 18 tables, published in Phys. Rev. D. Hepdata entry: https://www.hepdata.net/record/83660 All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2016-35

References in corpus (45)

• Planck 2015 results. XIII. Cosmological parameters
• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Theory of Dark Matter
• Secluded WIMP Dark Matter
• Scalar Dark Matter candidates
• Search for a dark photon in e+e- collisions at BABAR
• Improved Search for ${\bar{\nu }}_{\mu }\to {\bar{\nu }}_e$ Oscillations in the MiniBooNE Experiment
• Exploring Portals to a Hidden Sector Through Fixed Targets
• First Measurement of the Muon Neutrino Charged Current Quasielastic Double Differential Cross Section
• New Constraints and Prospects for sub-GeV Dark Matter Scattering off Electrons in Xenon
• The nuance Neutrino Simulation, and the Future
• The Neutrino Flux prediction at MiniBooNE
• Strong Constraints on Sub-GeV Dark Matter from SLAC Beam Dump E137
• Observing a light dark matter beam with neutrino experiments
• A Combined ${\nu }_{\mu }\to {\nu }_e$ and ${\bar{\nu }}_{\mu }\to {\bar{\nu }}_e$ Oscillation Analysis of the MiniBooNE Excesses
• Accelerating the Discovery of Light Dark Matter
• New Electron Beam-Dump Experiments to Search for MeV to few-GeV Dark Matter
• New constraints on light vectors coupled to anomalous currents
• Dark forces coupled to non-conserved currents
• The Liquid Scintillator Neutrino Detector and LAMPF Neutrino Source
• The MiniBooNE Detector
• Light spin-1/2 or spin-0 Dark Matter particles
• Measurement of the Neutrino Neutral-Current Elastic Differential Cross Section
• Light dark matter in neutrino beams: production modelling and scattering signatures at MiniBooNE, T2K and SHiP
• Search for vector mediator of Dark Matter production in invisible decay mode
• Testing Light Dark Matter Coannihilation With Fixed-Target Experiments
• Signatures of sub-GeV dark matter beams at neutrino experiments
• Leptophobic Dark Matter at Neutrino Factories
• Dark Matter Search in a Proton Beam Dump with MiniBooNE
• Hidden GeV-scale interactions of quarks
• Testing GeV-Scale Dark Matter with Fixed-Target Missing Momentum Experiments
• Light new physics in coherent neutrino-nucleus scattering experiments
• Measurement of ν_μand \barν_μinduced neutral current single ${\pi }^0$ production cross sections on mineral oil at E_νO(1 GeV)
• DAEdALUS and Dark Matter Detection
• The extended-track reconstruction for MiniBooNE
• The light U boson as the mediator of a new force, coupled to a combination of Q, B, L and dark matter
• Scattering of Dark Particles with Light Mediators
• Physics Motivation for a Pilot Dark Matter Search at Jefferson Laboratory
• Measurement of the Antineutrino Neutral-Current Elastic Differential Cross Section
• GeV-scale dark matter: production at the Main Injector
• Signatures of Pseudo-Dirac Dark Matter at High-Intensity Neutrino Experiments
• Dark matter beams at LBNF
• Probing sub-GeV dark sectors via high energy proton beams at LBNF/DUNE and MiniBooNE
• MeV-Scale Dark Matter Deep Underground

Cited by in corpus (99)

• Physics Beyond Colliders at CERN: Beyond the Standard Model Working Group Report
• Long-Lived Particles at the Energy Frontier: The MATHUSLA Physics Case
• The Dark Photon
• Dark matter search in missing energy events with NA64
• Updated MiniBooNE Neutrino Oscillation Results with Increased Data and New Background Studies
• Light Dark Matter at Neutrino Experiments
• The Present and Future Status of Heavy Neutral Leptons
• The Short-Baseline Neutrino Program at Fermilab
• Neutrino Non-Standard Interactions: A Status Report
• Inelastic Dark Matter at the LHC Lifetime Frontier: ATLAS, CMS, LHCb, CODEX-b, FASER, and MATHUSLA
• The Search for Feebly-Interacting Particles
• Strong New Limits on Light Dark Matter from Neutrino Experiments
• Millicharged particles in neutrino experiments
• Prospects for Beyond the Standard Model Physics Searches at the Deep Underground Neutrino Experiment
• Electron Ionization via Dark Matter-Electron Scattering and the Migdal Effect
• New Constraints on Millicharged Particles from Cosmic-ray Production
• Constraints on mediator-based dark matter and scalar dark energy models using $\sqrt{s}=13$ TeV $pp$ collision data collected by the ATLAS detector
• Revisiting the Dark Photon Explanation of the Muon Anomalous Magnetic Moment
• Searching in the dark: the hunt for the dark photon
• Searches for dark photons at accelerators
• Light Dark Matter from Inelastic Cosmic Ray Collisions
• Probing Light Dark Matter with a Hadrophilic Scalar Mediator
• Explaining the MiniBooNE excess by a decaying sterile neutrino with mass in the 250 MeV range
• Atmospheric Dark Matter and Xenon1T Excess
• Detecting Dark Matter with Far-Forward Emulsion and Liquid Argon Detectors at the LHC
• Mono-Neutrino at DUNE: New Signals From Neutrinophilic Thermal Dark Matter
• Boosted dark matter from diffuse supernova neutrinos
• A Dark Matter Interpretation of Excesses in Multiple Direct Detection Experiments
• Hunting On- and Off-Axis for Light Dark Matter with DUNE-PRISM
• Implications of BBN Bounds for Cosmic Ray Upscattered Dark Matter
• First Dark Matter Search Results From Coherent CAPTAIN-Mills
• Elastic and Inelastic Scattering of Cosmic-Rays on Sub-GeV Dark Matter
• Combined search for light dark matter with electron and muon beams at NA64
• Search for vector-like quarks in events with two oppositely charged leptons and jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Constraining Sterile Neutrino Interpretations of the LSND and MiniBooNE Anomalies with Coherent Neutrino Scattering Experiments
• Probing the Higgs Portal at the Fermilab Short-Baseline Neutrino Experiments
• Sensitivity of the COHERENT Experiment to Accelerator-Produced Dark Matter
• Searching for Physics Beyond the Standard Model in an Off-Axis DUNE Near Detector
• LSND Constraints on the Higgs Portal
• Dark Sector Production via Proton Bremsstrahlung
• Two-Higgs doublet solution to the LSND, MiniBooNE and muon $g-2$ anomalies
• Search for Dark-Matter-Nucleon Interactions with a Dark Mediator in PandaX-4T
• Probing Invisible Vector Meson Decays with NA64 and LDMX
• Millicharged Cosmic Rays and Low Recoil Detectors
• On sub-GeV Dark Matter Production at Fixed-Target Experiments
• Hunting sub-GeV dark matter with NO$\nu$A near detector
• New production channels for light dark matter in hadronic showers
• Dark sector-photon interactions in proton-beam experiments
• Exclusion limits on Dark Matter-Neutrino Scattering Cross-section
• Scale Invariant FIMP Miracle
• Hadrophilic Dark Sectors at the Forward Physics Facility
• FLArE up dark sectors with EM form factors at the LHC Forward Physics Facility
• Solutions to the MiniBooNE Anomaly from New Physics in Charged Meson Decays
• Resonant or asymmetric: The status of sub-GeV dark matter
• Severe Constraints on New Physics Explanations of the MiniBooNE Excess
• Model Independent Bounds on the Non-Oscillatory Explanations of the MiniBooNE Excess
• Discovering Dark Matter at the LHC through Its Nuclear Scattering in Far-Forward Emulsion and Liquid Argon Detectors
• The hunt for sub-GeV dark matter at neutrino facilities: a survey of past and present experiments
• Heating Neutron Stars with Inelastic Dark Matter and Relativistic Targets
• Searching for Boosted Dark Matter via Dark-Strahlung
• First Leptophobic Dark Matter Search from Coherent CAPTAIN-Mills
• Opportunities for probing $U(1{)}_{T3R}$ with light mediators
• Renormalizable Models of Flavor-Specific Scalars
• Searches for long-lived dark photons at proton accelerator experiments
• Accelerated Light Dark Matter-Earth Inelastic Scattering in Direct Detection
• BSM Targets at a "Target-less DUNE"
• Review of Dark Matter
• Dark matter search with the BDX-MINI experiment
• Search for light dark matter from atmosphere in PandaX-4T
• Probing the flavor-specific scalar mediator for the muon $(g-2)$ deviation, the proton radius puzzle and the light dark matter production
• Extending the Reach of Leptophilic Boson Searches at DUNE and MiniBooNE with Bremsstrahlung and Resonant Production
• Prospect of undoped inorganic crystals at 77 Kelvin for low-mass dark matter search at Spallation Neutron Source
• Neutrino Masses and Mixing: A Little History for a Lot of Fun
• Probing the dark sector with nuclear transition photons
• Sub-GeV dark matter and nano-Hertz gravitational waves from a classically conformal dark sector
• Milli-Magnetic Monopole Dark Matter and the Survival of Galactic Magnetic Fields
• A Snowmass Whitepaper: Dark Matter Production at Intensity-Frontier Experiments
• Energy and Flavor Discrimination Using Precision Time Structure in On-Axis Neutrino Beams
• Prospects for Dark Matter Search at the Super c-tau Factory
• Characterizing Dark Matter Signals with Missing Momentum Experiments
• DUNE prospect for leptophobic dark matter
• Dark Matter as a Solution to Muonic Puzzles
• Search for millicharged particles in proton-proton collisions at $\sqrt{s}=13.6$ TeV
• Uncovering the Root of LEFT in SMEFT
• Complementarity between Cosmic String Gravitational Waves and long-lived particle searches in a laboratory
• Dark states with electromagnetic form factors at electron colliders
• Light dark matter searches with positrons
• Inelastic Dark Matter at the Fermilab Short Baseline Neutrino Program
• DUNE potential for sub-GeV dark matter in proton beam dump mode
• Enhancing the Sensitivity to Seesaw Predictions in Gauged $B-L$ Scenarios
• The Forward Physics Facility at the High-Luminosity LHC
• Scientific Opportunities at the ARIEL Electron Linac
• The Dark Photon: a 2026 Perspective
• Atmospheric resonant production for light dark sectors
• Naturally Resonant Dark Matter from Extra Dimensions
• Study of sub-GeV Dipolar Dark States at SND@LHC within Invisible Bounds on Meson Decays
• First search for dark-trident processes using the MicroBooNE detector
• Probing inelastic sub-GeV dark matter at the DUNE near detector
• MiniBooNE Neutrino Oscillation Search Results and Predicted Background Events