Search for long-lived neutral particles in $pp$ collisions at $\sqrt{s}$ = 13 TeV that decay into displaced hadronic jets in the ATLAS calorimeter

Abstract

This paper describes a search for pairs of neutral, long-lived particles decaying in the ATLAS calorimeter. Long-lived particles occur in many extensions to the Standard Model and may elude searches for new promptly decaying particles. The analysis considers neutral, long-lived scalars with masses between 5 GeV and 400 GeV, produced from decays of heavy bosons with masses between 125 GeV and 1000 GeV, where the long-lived scalars decay into Standard Model fermions. The analysis uses either 10.8 fb${}^{-1}$ or 33.0 fb${}^{-1}$ of data (depending on the trigger) recorded in 2016 at the LHC with the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV. No significant excess is observed, and limits are reported on the production cross section times branching ratio as a function of the proper decay length of the long-lived particles.

arXiv commentComments: 47 pages in total, author list starting page 31, 10 figures, 3 tables, submitted to EPJC. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2017-25

References in corpus (59)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• The anti-k_t jet clustering algorithm
• An Introduction to PYTHIA 8.2
• A Brief Introduction to PYTHIA 8.1
• Parton distributions for the LHC
• Asymptotic formulae for likelihood-based tests of new physics
• Parton distributions with LHC data
• The ATLAS Simulation Infrastructure
• Theories with Gauge-Mediated Supersymmetry Breaking
• R-parity violating supersymmetry
• Echoes of a Hidden Valley at Hadron Colliders
• Performance of the ATLAS Trigger System in 2015
• TMVA - Toolkit for Multivariate Data Analysis
• The Twin Higgs: Natural Electroweak Breaking from Mirror Symmetry
• Asymmetric Dark Matter
• Production and Integration of the ATLAS Insertable B-Layer
• Luminosity determination in pp collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector at the LHC
• Big Bang Nucleosynthesis Constraints on Hadronically and Electromagnetically Decaying Relic Neutral Particles
• Jet energy scale measurements and their systematic uncertainties in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Mini-Split
• Non-Abelian Dark Sectors and Their Collider Signatures
• Discovering the Higgs Through Highly-Displaced Vertices
• Measurement of the Inelastic Proton-Proton Cross Section at $\sqrt{s}=13$ TeV with the ATLAS Detector at the LHC
• Folded Supersymmetry and the LEP Paradox
• Dynamical Dark Matter: I. Theoretical Overview
• Stealth Supersymmetry
• Simply Unnatural Supersymmetry
• Nonstandard Higgs Boson Decays
• Heavy neutrino searches at the LHC with displaced vertices
• Search for massive, long-lived particles using multitrack displaced vertices or displaced lepton pairs in pp collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• A Quirky Little Higgs Model
• Search for long-lived, massive particles in events with displaced vertices and missing transverse momentum in $\sqrt{s}$ = 13 TeV $pp$ collisions with the ATLAS detector
• Naturalness and Higgs Decays in the MSSM with a Singlet
• Search for long-lived particles that decay into final states containing two electrons or two muons in proton-proton collisions at sqrt(s) = 8 TeV
• Search for long-lived, weakly interacting particles that decay to displaced hadronic jets in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
• Search for long-lived neutral particles decaying into lepton jets in proton--proton collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• A Stealth Supersymmetry Sampler
• Characterisation and mitigation of beam-induced backgrounds observed in the ATLAS detector during the 2011 proton-proton run
• Probing Baryogenesis with Displaced Vertices at the LHC
• Search for pair-produced long-lived neutral particles decaying in the ATLAS hadronic calorimeter in $pp$ collisions at $\sqrt{s}$ = 8 TeV
• Search for long-lived particles produced in $pp$ collisions at $\sqrt{s}=13$ TeV that decay into displaced hadronic jets in the ATLAS muon spectrometer
• Search for a light Higgs boson decaying to long-lived weakly-interacting particles in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector
• Search for non-pointing and delayed photons in the diphoton and missing transverse momentum final state in 8 TeV $pp$ collisions at the LHC using the ATLAS detector
• Shedding Light on Neutrino Masses with Dark Forces
• Triggers for displaced decays of long-lived neutral particles in the ATLAS detector
• A Quirky Probe of Neutral Naturalness
• Search in leptonic channels for heavy resonances decaying to long-lived neutral particles
• Distinguishing Dynamical Dark Matter at the LHC
• LHC Signatures of a Minimal Supersymmetric Hidden Valley
• Search for resonant pair production of neutral long-lived particles decaying to bbbar in ppbar collisions at sqrt(s)=1.96 TeV
• Search for long-lived particles decaying into displaced jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Search for long-lived particles in final states with displaced dimuon vertices in $pp$ collisions at $\sqrt{s}=$ 13 TeV with the ATLAS detector
• Search for long-lived particles in events with photons and missing energy in proton-proton collisions at sqrt(s) = 7 TeV
• Search for long-lived particles with displaced vertices in multijet events in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Search for new long-lived particles at $\sqrt{s}=$ 13 TeV
• Search for heavy metastable particles decaying to jet pairs in pp collisions at sqrt{s} = 1.96 TeV
• Beam-induced and cosmic-ray backgrounds observed in the ATLAS detector during the LHC 2012 proton-proton running period
• Search for the production of a long-lived neutral particle decaying within the ATLAS hadronic calorimeter in association with a $Z$ boson from $pp$ collisions at $\sqrt{s}=13$ TeV
• Search for new physics with long-lived particles decaying to photons and missing energy in pp collisions at sqrt(s) = 7 TeV

Cited by in corpus (37)

• Feebly-Interacting Particles:FIPs 2020 Workshop Report
• Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider
• Dijet resonance search with weak supervision using $\sqrt{s}=13$ TeV $pp$ collisions in the ATLAS detector
• A deep neural network to search for new long-lived particles decaying to jets
• Software and computing for Run 3 of the ATLAS experiment at the LHC
• Search for long-lived particles using displaced jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Search for long-lived particles using nonprompt jets and missing transverse momentum with proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Search for long-lived neutral particles produced in $pp$ collisions at $\sqrt{s}=13$ TeV decaying into displaced hadronic jets in the ATLAS inner detector and muon spectrometer
• Implications of Feebly Interacting Dark Sector on Neutron Star Properties and Constraints from GW170817
• Search for displaced leptons in $\sqrt{s}=13$ TeV $pp$ collisions with the ATLAS detector
• Search for light long-lived neutral particles produced in $pp$ collisions at $\sqrt{s}=$ 13 TeV and decaying into collimated leptons or light hadrons with the ATLAS detector
• Performance of the ATLAS Level-1 topological trigger in Run 2
• Unleashing the full power of LHCb to probe Stealth New Physics
• Collider Searches for Dark Matter through the Higgs Lens
• Enhancing Sensitivities to Long-lived Particles with High Granularity Calorimeters at the LHC
• Exotic Higgs Decays
• Search for long-lived particles decaying to leptons with large impact parameter in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Hypercharged Naturalness
• Resurrecting the Fraternal Twin WIMP Miracle
• ATLAS searches for additional scalars and exotic Higgs boson decays with the LHC Run 2 dataset
• Probing Long-lived Particles at Higgs Factories
• Determining the lifetime of long-lived particles at the HL-LHC
• Enhanced Long-Lived Dark Photon Signals at the LHC
• Baryogenesis and Dark Matter from Freeze-In
• Leptons lurking in semi-visible jets at the LHC
• Search for a light $Z^{\prime }$ at LHC in a neutrinophilic $U(1)$ model
• Demystifying Freeze-In Dark Matter at the LHC
• Freeze-in and Freeze-out of Dark Matter with Charged Long-lived Partners
• Exploring the lifetime and cosmic frontier with the MATHUSLA detector
• Exotic Higgs decays into displaced jets at the LHeC
• Machine-Learning Performance on Higgs-Pair Production Associated with Dark Matter at the LHC
• Search for strongly interacting massive particles generating trackless jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Identifying Exclusive Displaced Hadronic Signatures in the Forward Region of the LHC
• Search for events with one displaced vertex from long-lived neutral particles decaying into hadronic jets in the ATLAS muon spectrometer in $pp$ collisions at $\sqrt{s}=13$ TeV
• Search for heavy neutral leptons in decays of W bosons produced in 13 TeV pp collisions using prompt signatures in the ATLAS detector
• Displaced fat-jets and tracks to probe boosted right-handed neutrinos in the $U(1{)}_{B-L}$ model
• Searches for new physics with unconventional signatures at ATLAS and CMS