Search for new phenomena in final states with two leptons and one or no $b$-tagged jets at $\sqrt{s}=13$ TeV using the ATLAS detector

Abstract

A search for new phenomena is presented in final states with two leptons and one or no $b$-tagged jets. The event selection requires the two leptons to have opposite charge, the same flavor (electrons or muons), and a large invariant mass. The analysis is based on the full Run-2 proton-proton collision dataset recorded at a center-of-mass energy of $\sqrt{s}=13$ TeV by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 139 fb${}^{-1}$. No significant deviation from the expected background is observed in the data. A four-fermion contact interaction between two quarks ($b,s$) and two leptons ($ee$ or $\mu \mu$), inspired by the $B$-meson decay anomalies, is used as a benchmark signal model. This model is characterized by the energy scale and coupling, $\Lambda$ and $g_{\ast }$ respectively. Contact interactions with $\Lambda /g_{\ast }$ lower than 2.0 (2.4) TeV are excluded for electrons (muons) at the 95% confidence level, still far below the value which is favored by the $B$-meson decay anomalies. In addition, model-independent limits are set as a function of the selection on the dilepton invariant mass, which allows the results to be reinterpreted in other signal scenarios.

arXiv comment32 pages in total, author list starting page 12, 4 figures, 1 table, submitted to PRL. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2018-16/

References in corpus (65)

• 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
• New Generation of Parton Distributions with Uncertainties from Global QCD Analysis
• Asymptotic formulae for likelihood-based tests of new physics
• A general framework for implementing NLO calculations in shower Monte Carlo programs: the POWHEG BOX
• A New Method for Combining NLO QCD with Shower Monte Carlo Algorithms
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• Parton distributions for the LHC Run II
• New parton distributions for collider physics
• Event generation with SHERPA 1.1
• The ATLAS Simulation Infrastructure
• PDF4LHC recommendations for LHC Run II
• Scattering Amplitudes with Open Loops
• Herwig 7.0 / Herwig++ 3.0 Release Note
• Precision Electroweak Measurements on the Z Resonance
• A parton shower algorithm based on Catani-Seymour dipole factorisation
• QCD Matrix Elements + Parton Showers
• Comix, a new matrix element generator
• Event Generation with Sherpa 2.2
• PHOTOS Monte Carlo: a precision tool for QED corrections in Z and W decays
• QCD matrix elements + parton showers: The NLO case
• High-precision QCD at hadron colliders: electroweak gauge boson rapidity distributions at NNLO
• QCD matrix elements and truncated showers
• Collier: a fortran-based Complex One-Loop LIbrary in Extended Regularizations
• Test of lepton universality with $B^0\to K^{\ast 0}{\ell }^{+}{\ell }^{-}$ decays
• Single-top hadroproduction in association with a W boson
• Muon reconstruction performance of the ATLAS detector in proton--proton collision data at $\sqrt{s}$=13 TeV
• A critical appraisal of NLO+PS matching methods
• Production and Integration of the ATLAS Insertable B-Layer
• OpenLoops 2
• Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1
• 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
• Angular analysis of the $B^0\to K^{\ast 0}{\mu }^{+}{\mu }^{-}$ decay using $3\,\mbox{fb}^{-1}$ of integrated luminosity
• NLO vector-boson production matched with shower in POWHEG
• Performance of $b$-Jet Identification in the ATLAS Experiment
• Measurement of the $Z/{\gamma }^{\ast }$ boson transverse momentum distribution in $pp$ collisions at $\sqrt{s}$ = 7 TeV with the ATLAS detector
• Search for lepton-universality violation in $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• Jet reconstruction and performance using particle flow with the ATLAS Detector
• ATLAS $b$-jet identification performance and efficiency measurement with $t\bar{t}$ events in $pp$ collisions at $\sqrt{s}=13$ TeV
• Performance of electron and photon triggers in ATLAS during LHC Run 2
• Search for high-mass dilepton resonances in pp collisions at sqrt(s) = 8 TeV with the ATLAS detector
• Parton distributions incorporating QED contributions
• Differential branching fractions and isospin asymmetries of $B\to K^{(\ast )}{\mu }^{+}{\mu }^{-}$ decays
• Muon reconstruction and identification efficiency in ATLAS using the full Run 2 $pp$ collision data set at $\sqrt{s}=13$ TeV
• Jet energy scale and resolution measured in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Performance of the ATLAS muon triggers in Run 2
• NLO matrix elements and truncated showers
• Angular analysis and differential branching fraction of the decay $B_s^0\to \varphi {\mu }^{+}{\mu }^{-}$
• Search for new high-mass phenomena in the dilepton final state using 36 fb${}^{-1}$ of proton-proton collision data at $\sqrt{s}$ = 13 TeV with the ATLAS detector
• Measurement of $CP$-averaged observables in the $B^0\to K^{\ast 0}{\mu }^{+}{\mu }^{-}$ decay
• Matching Tree-Level Matrix Elements with Interleaved Showers
• Emerging patterns of New Physics with and without Lepton Flavour Universal contributions
• High-$p_T$ dilepton tails and flavour physics
• Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
• Test of lepton-flavor universality in $B\to K^{\ast }{\ell }^{+}{\ell }^{-}$ decays at Belle
• A meta-analysis of parton distribution functions
• Test of lepton flavor universality and search for lepton flavor violation in $B\to K\ell \ell$ decays
• Search for a heavy charged boson in events with a charged lepton and missing transverse momentum from $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Test of lepton universality with ${\Lambda }_b^0\to p{K}^{-}{\ell }^{+}{\ell }^{-}$ decays
• Searching for New Physics with $b\bar{b}{\ell }^{+}{\ell }^{-}$ Contact Interactions
• New flavor physics in di- and tri-lepton events from single-top at the LHC and beyond
• Establishing a Search for $b\to s{\ell }^{+}{\ell }^{-}$ Anomalies at the LHC

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• Third order fiducial predictions for Drell-Yan at the LHC
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