Search for dark matter produced in association with bottom or top quarks in $\sqrt{s}$ = 13 TeV pp collisions with the ATLAS detector

Abstract

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and missing transverse momentum are considered. The analysis uses 36.1 $f{b}^{-1}$ of proton-proton collision data recorded by the ATLAS experiment at $\sqrt{s}$ = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are interpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour-neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross-section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour-charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements.

52 pages in total, author list starting page 36, 8 figures, 9 tables, submitted to EPJC, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/SUSY-2016-18/

References in corpus (27)

• 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
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Parton distributions for the LHC
• New parton distributions for collider physics
• Event generation with SHERPA 1.1
• Results from a search for dark matter in the complete LUX exposure
• A parton shower algorithm based on Catani-Seymour dipole factorisation
• 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-
• Dark Matter Results from First 98.7-day Data of PandaX-II Experiment
• Next-to-next-to-leading-order collinear and soft gluon corrections for t-channel single top quark production
• NNLL resummation for s-channel single top quark production
• Luminosity determination in pp collisions at $\sqrt{s}$ = 8 TeV using the ATLAS detector at the LHC
• Electron and photon energy calibration with the ATLAS detector using LHC Run 1 data
• HistFitter software framework for statistical data analysis
• Colour reconnections in Herwig++
• Scalar Simplified Models for Dark Matter
• Search for direct top-squark pair production in final states with two leptons in pp collisions at sqrt(s)=8TeV with the ATLAS detector
• Flavored Dark Matter and the Galactic Center Gamma-Ray Excess
• Search for a scalar partner of the top quark in the jets plus missing transverse momentum final state at $\sqrt{s}$=13 TeV with the ATLAS detector
• Search for dark matter in events with heavy quarks and missing transverse momentum in $pp$ collisions with the ATLAS detector
• Search for Dark Matter Produced in Association with a Higgs Boson Decaying to $b\bar{b}$ using 36 fb${}^{-1}$ of $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS Detector
• Determining the CP nature of spin-0 mediators in associated production of dark matter and $t\bar{t}$ pairs
• Search for supersymmetry in events with $b$-tagged jets and missing transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Search for dark matter produced in association with heavy-flavor quarks in proton-proton collisions at sqrt(s) = 13 TeV
• Search for new physics in the monophoton final state in proton-proton collisions at sqrt(s) = 13 TeV

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• Perspectives and Outlook from HEP Window on the Universe