Search for supersymmetry in final states with missing transverse momentum and three or more $b$-jets in 139 fb${}^{-1}$ of proton$-$proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

Abstract

A search for supersymmetry involving the pair production of gluinos decaying via off-shell third-generation squarks into the lightest neutralino (${\tilde{\chi }}_1^0$) is reported. It exploits LHC proton$-$proton collision data at a centre-of-mass energy $\sqrt{s}=13$ TeV with an integrated luminosity of 139 fb${}^{-1}$ collected with the ATLAS detector from 2015 to 2018. The search uses events containing large missing transverse momentum, up to one electron or muon, and several energetic jets, at least three of which must be identified as containing $b$-hadrons. Both a simple kinematic event selection and an event selection based upon a deep neural-network are used. No significant excess above the predicted background is found. In simplified models involving the pair production of gluinos that decay via off-shell top (bottom) squarks, gluino masses less than 2.44 TeV (2.35 TeV) are excluded at 95% CL for a massless ${\tilde{\chi }}_1^0$. Limits are also set on the gluino mass in models with variable branching ratios for gluino decays to $b\bar{b}{\tilde{\chi }}_1^0$, $t\bar{t}{\tilde{\chi }}_1^0$ and $t\bar{b}{\tilde{\chi }}_1^{-}$ / $\bar{t}b{\tilde{\chi }}_1^{+}$.

arXiv comment59 pages in total, author list starting page 43, 13 figures, 13 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/SUSY-2018-30/

References in corpus (69)

• 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
• A Brief Introduction to PYTHIA 8.1
• FastJet user manual
• Asymptotic formulae for likelihood-based tests of new physics
• A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX
• Parton distributions for the LHC Run II
• Event generation with SHERPA 1.1
• Parton distributions with LHC data
• The ATLAS Simulation Infrastructure
• Top++: a program for the calculation of the top-pair cross-section at hadron colliders
• Searching for Exotic Particles in High-Energy Physics with Deep Learning
• Tuning Monte Carlo Generators: The Perugia Tunes
• QCD matrix elements + parton showers: The NLO case
• Performance of the ATLAS Trigger System in 2015
• Vector boson production at hadron colliders: a fully exclusive QCD calculation at NNLO
• Two-loop soft anomalous dimensions for single top quark associated production with a W- or H-
• -- HATHOR -- HAdronic Top and Heavy quarks crOss section calculatoR
• Jet Trimming
• Muon reconstruction performance of the ATLAS detector in proton--proton collision data at $\sqrt{s}$=13 TeV
• Next-to-next-to-leading-order collinear and soft gluon corrections for t-channel single top quark production
• Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1
• Natural SUSY Endures
• Performance of pile-up mitigation techniques for jets in $pp$ collisions at $\sqrt{s}=8$ TeV using the ATLAS detector
• Electron and photon performance measurements with the ATLAS detector using the 2015-2017 LHC proton-proton collision data
• Simplified Models for LHC New Physics Searches
• Squark and Gluino Production at Hadron Colliders
• Threshold resummation for squark-antisquark and gluino-pair production at the LHC
• Simplified Models for a First Characterization of New Physics at the LHC
• ATLAS $b$-jet identification performance and efficiency measurement with $t\bar{t}$ events in $pp$ collisions at $\sqrt{s}=13$ TeV
• Squark and gluino hadroproduction
• Soft gluon resummation for the production of gluino-gluino and squark-antisquark pairs at the LHC
• Jet energy scale measurements and their systematic uncertainties in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Soft-gluon resummation for squark and gluino hadroproduction
• HATHOR for single top-quark production: Updated predictions and uncertainty estimates for single top-quark production in hadronic collisions
• Muon reconstruction and identification efficiency in ATLAS using the full Run 2 $pp$ collision data set at $\sqrt{s}=13$ TeV
• Squark and gluino production cross sections in pp collisions at $\sqrt{s}$ = 13, 14, 33 and 100 TeV
• ATLAS data quality operations and performance for 2015-2018 data-taking
• Performance of missing transverse momentum reconstruction with the ATLAS detector using proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Jet energy scale and resolution measured in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Electron and photon energy calibration with the ATLAS detector using LHC Run 1 data
• HistFitter software framework for statistical data analysis
• Parameterized Machine Learning for High-Energy Physics
• Electron reconstruction and identification in the ATLAS experiment using the 2015 and 2016 LHC proton-proton collision data at $\sqrt{s}$ = 13 TeV
• Search for supersymmetry in proton-proton collisions at 13 TeV in final states with jets and missing transverse momentum
• Performance of the ATLAS Track Reconstruction Algorithms in Dense Environments in LHC Run 2
• Searching for Directly Decaying Gluinos at the Tevatron
• Performance of jet substructure techniques for large-R jets in proton-proton collisions at sqrt(s) = 7 TeV using the ATLAS detector
• Search for supersymmetry at $\sqrt{s}=13$ TeV in final states with jets and two same-sign leptons or three leptons with the ATLAS detector
• Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton-proton collisions at the LHC
• Search for new phenomena with the MT2 variable in the all-hadronic final state produced in proton-proton collisions at sqrt(s) = 13 TeV
• Searches for physics beyond the standard model with the $M_{T2}$ variable in hadronic final states with and without disappearing tracks in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Characterisation and mitigation of beam-induced backgrounds observed in the ATLAS detector during the 2011 proton-proton run
• 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
• Jets from Jets: Re-clustering as a tool for large radius jet reconstruction and grooming at the LHC
• Search for supersymmetry in final states with two same-sign or three leptons and jets using 36 fb${}^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collision data with the ATLAS detector
• In situ calibration of large-$R$ jet energy and mass in 13 TeV proton-proton collisions with the ATLAS detector
• Search for supersymmetry in final states with missing transverse momentum and multiple $b$-jets in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for top squark production in fully-hadronic final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Search for pair production of gluinos decaying via stop and sbottom in events with $b$-jets and large missing transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for supersymmetry in proton-proton collisions at 13 TeV using identified top quarks
• In-medium covariant propagator of baryons under a strong magnetic field: effect of the intrinsic magnetic moments
• Measurements of fiducial cross-sections for $t\bar{t}$ production with one or two additional $b$-jets in $pp$ collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector
• Search for physics beyond the standard model in events with jets and two same-sign or at least three charged leptons in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Measurement of Higgs boson decay into $b$-quarks in associated production with a top-quark pair in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for new phenomena in final states with large jet multiplicities and missing transverse momentum using $\sqrt{(}s)=13$ TeV proton$-$proton collisions recorded by ATLAS in Run 2 of the LHC
• Measurements of the production cross-section for a $Z$ boson in association with $b$-jets in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for supersymmetry in pp collisions at $\sqrt{s}=$ 13 TeV with 137 fb${}^{-1}$ in final states with a single lepton using the sum of masses of large-radius jets
• Measurements of jet observables sensitive to $b$-quark fragmentation in $t\bar{t}$ events at the LHC with the ATLAS detector

Cited by in corpus (10)

• The quest to discover supersymmetry at the ATLAS experiment
• Combining Resonant and Tail-based Anomaly Detection
• The Muon Magnetic Moment and Physics Beyond the Standard Model
• Les Houches guide to reusable ML models in LHC analyses
• NNLL-fast 2.0: Coloured Sparticle Production at the LHC Run 3 with $\sqrt{S}$ = 13.6 TeV
• Machine Learning Approaches to Top Quark Flavor-Changing Four-Fermion Interactions in Trilepton Signals at the LHC
• Classifier Surrogates: Sharing AI-based Searches with the World
• 2B or not 2B, a study of bottom-quark-philic semi-visible jets
• Learning Selection Cuts With Gradients
• Triplet fermion WIMP dark matter in the general supersymmetric Georgi-Machacek model