0000000000065999

AUTHOR

L. F. Flores

showing 6 related works from this author

Observation of light-by-light scattering in ultraperipheral Pb+Pb collisions with the ATLAS detector

2019

This Letter describes the observation of the light-by-light scattering process, γγ→γγ, in Pb+Pb collisions at √sNN=5.02  TeV. The analysis is conducted using a data sample corresponding to an integrated luminosity of 1.73  nb−1, collected in November 2018 by the ATLAS experiment at the LHC. Light-by-light scattering candidates are selected in events with two photons produced exclusively, each with transverse energy EγT>3  GeV and pseudorapidity |ηγ|<2.4, diphoton invariant mass above 6 GeV, and small diphoton transverse momentum and acoplanarity. After applying all selection criteria, 59 candidate events are observed for a background expectation of 12±3 events. The observed excess of events…

Photonheavy ion: scatteringmass spectrum: (2photon)Physics::Instrumentation and Detectorsmeasured [channel cross section]General Physics and Astronomytransverse energy [photon]nucl-ex01 natural sciencesLight scatteringHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)Scattering processPseudorapidities[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Invariant massCollisionsNuclear Experiment (nucl-ex)Nuclear ExperimentNuclear Experimentelastic scattering [photon photon]Physicsphoton: transverse energyproton–proton collisionsLarge Hadron ColliderSettore FIS/01 - Fisica SperimentaleATLAS:Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 [VDP]CERN LHC CollPseudorapidityTransverse momentalight-by-light scatteringLHCchannel cross section: measuredParticle Physics - Experimentrelativistic heavy-ion collisionsjets(2photon) [mass spectrum]Transverse energyCiências Naturais::Ciências Físicas530 PhysicsAstrophysics::High Energy Astrophysical Phenomena:Ciências Físicas [Ciências Naturais]FOS: Physical sciencesATLAS experimentddc:500.2LHC ATLAS High Energy Physicstransverse momentumplanarity[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]Relativistic heavy ions530AcoplanarityNuclear physicsscattering [heavy ion]Delbrück scattering0103 physical sciencesStandard deviationNuclear Physics - Experimentddc:5305020 GeV-cms/nucleonSelection criteria010306 general physicsperipheralCiencias Exactastwo-photon [mass spectrum]Integrated luminosityleadScience & Technologyhep-exrapidity [photon]Scatteringbackground:Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 [VDP]Físicaphoton: rapidityElementary Particles and FieldsHigh Energy Physics::Experimentphoton photon: elastic scatteringmass spectrum: two-photonexperimental results
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Observation of electroweak W±Z boson pair production in association with two jets in pp collisions at s=13 TeV with the ATLAS detector

2019

An observation of electroweak W±Z production in association with two jets in proton–proton collisions is presented. The data collected by the ATLAS detector at the Large Hadron Collider in 2015 and 2016 at a centre-of-mass energy of s=13 TeV are used, corresponding to an integrated luminosity of 36.1fb−1 . Events containing three identified leptons, either electrons or muons, and two jets are selected. The electroweak production of W±Z bosons in association with two jets is measured with an observed significance of 5.3 standard deviations. A fiducial cross-section for electroweak production including interference effects and for a single leptonic decay mode is measured to be σWZjj−EW=0.57−0…

PhysicsNuclear and High Energy PhysicsParticle physicsMuonLuminosity (scattering theory)Large Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyElectroweak interaction7. Clean energy01 natural sciencesPair productionmedicine.anatomical_structureAtlas (anatomy)0103 physical sciencesmedicineHigh Energy Physics::Experiment010306 general physicsLeptonBosonPhysics Letters B
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Combination of Searches for Invisible Higgs Boson Decays with the ATLAS Experiment

2019

Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H → invisible decays where H is produced according to the standard model via vector boson fusion, Z(ℓℓ)H, and W/Z(had)H, all performed with the ATLAS detector using 36.1  fb⁻¹ of pp collisions at a center-of-mass energy of √s = 13  TeV at the LHC. In combination with the results at √s = 7 and 8 TeV, an exclusion limit on the H → invisible branching ratio of 0.26(0.17-0.05+0.07) at 95% confidence level is observed (expected).

WIMP nucleon: scatteringMATÉRIA ESCURA13000 GeV-cmsGeneral Physics and Astronomy01 natural sciencesWIMP: dark matterVector bosonHigh Energy Physics - Experimentdark matter [WIMP]Subatomär fysikHiggs particle: hadroproductionHigh Energy Physics - Experiment (hep-ex)vector boson: fusionSubatomic Physicsscattering [p p]S126.7[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]GeneralLiterature_REFERENCE(e.g.dictionariesencyclopediasglossaries)Z0: hadronic decayvector boson: associated productionPhysicsS030DMPLarge Hadron Colliderhadronic decay [Z0]ATLAS experimentSettore FIS/01 - Fisica SperimentaleConfidence levelsBranching ratioATLAS:Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 [VDP]Vector bosonmedicine.anatomical_structureThe standard modelCERN LHC CollHiggs particle: branching ratio: upper limitHiggs bosonLHCgamma-ray excesscolliding beams [p p]Particle Physics - ExperimentS126:Desig=7Particle physicsp p: scattering530 PhysicsCiências Naturais::Ciências FísicasHiggs bosonDark matter:Ciências Físicas [Ciências Naturais]FOS: Physical sciencesATLAS experimentHiggs particle: invisible decaybranching ratio: upper limit [Higgs particle]LHC ATLAS High Energy Physicsddc:500.2fusion [vector boson]530Standard ModelmodelsParticle dark matterAtlas (anatomy)0103 physical sciencesmedicineDark matterddc:530High Energy Physics010306 general physicshadronic decay [W]Ciencias ExactasATLAS CollaborationW: hadronic decayScience & TechnologyBranching fractionscattering [WIMP nucleon]hep-exATLAS detectorsHigh Energy Physics::Phenomenology:Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 [VDP]Físicaleptonic decay [Z0]Higgs Boson decayInvisible decaysExperimental High Energy PhysicsZ0: leptonic decayExtensions of Higgs sectorDark matter particlesElementary Particles and Fieldshadroproduction [Higgs particle]associated production [vector boson]High Energy Physics::ExperimentHadron-hadron collisionsstatisticalp p: colliding beamsinvisible decay [Higgs particle]experimental results
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Search for a heavy charged boson in events with a charged lepton and missing transverse momentum from pp collisions at s=13  TeV with the ATLAS detec…

2019

A search for a heavy charged-boson resonance decaying into a charged lepton (electron or muon) and a neutrino is reported. A data sample of 139  fb−1 of proton-proton collisions at √s=13  TeV collected with the ATLAS detector at the LHC during 2015–2018 is used in the search. The observed transverse mass distribution computed from the lepton and missing transverse momenta is consistent with the distribution expected from the Standard Model, and upper limits on the cross section for pp→W′→lν are extracted (l=e or μ). These vary between 1.3 pb and 0.05 fb depending on the resonance mass in the range between 0.15 and 7.0 TeV at 95% confidence level for the electron and muon channels combined. …

PhysicsParticle physicsGauge bosonLarge Hadron ColliderMuon010308 nuclear & particles physicsHigh Energy Physics::Phenomenology01 natural sciencesPair production0103 physical sciencesTransverse massHigh Energy Physics::ExperimentNeutrino010306 general physicsLeptonBosonPhysical Review D
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Observation of Electroweak Production of a Same-Sign W Boson Pair in Association with Two Jets in pp Collisions at s=13  TeV with the ATLAS Detector

2019

This Letter presents the observation and measurement of electroweak production of a same-sign W boson pair in association with two jets using 36.1  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13  TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed in the detector fiducial phase-space region, defined by the presence of two same-sign leptons, electron or muon, and at least two jets with a large invariant mass and rapidity difference. A total of 122 candidate events are observed for a background expectation of 69±7 events, corresponding to an observed signal significance of 6.5 standard deviations. The measured fiducial s…

PhysicsParticle physicsLarge Hadron ColliderMuonElectroweak interactionGeneral Physics and Astronomy01 natural sciences0103 physical sciencesHigh Energy Physics::ExperimentRapidityInvariant massNuclear Experiment010306 general physicsEnergy (signal processing)BosonLeptonPhysical Review Letters
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Measurement of the production cross section for a Higgs boson in association with a vector boson in the H → WW⁎ → ℓνℓν channel in pp collisions at s=…

2019

A measurement of the Higgs boson production cross sections via associated WH and ZH production using H -> WW* -> l nu l nu decays, where l stands for either an electron or a muon, is presente ...

PhysicsNuclear and High Energy PhysicsParticle physicsLarge Hadron ColliderMuonPhysics::Instrumentation and Detectors010308 nuclear & particles physicsAtlas detectorHigh Energy Physics::PhenomenologyElectron01 natural sciencesVector boson0103 physical sciencesHiggs bosonHigh Energy Physics::Experiment010306 general physicsPhysics Letters B
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