0000000000503450

AUTHOR

M. A. Völkl

showing 10 related works from this author

The ALICE Transition Radiation Detector: Construction, operation, and performance

2018

The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 GeV/$c$ in p-Pb collisions and the resolution at high transverse momentum improves by about 40% when including the TRD information in track reconstruction. The triggering capability is demonstrated both …

Physics - Instrumentation and Detectors:Kjerne- og elementærpartikkelfysikk: 431 [VDP]TRPhysics::Instrumentation and DetectorsCOLLIDING BEAM EXPERIMENT; ELECTRON IDENTIFICATION; DRIFT CHAMBERS; TRD PROTOTYPES; ENERGY-LOSS; GEV/C; COLLISIONS; PIONSparticle identification [electron]Ionisation energy loTracking (particle physics)Transition radiation detector ; Multi-wire proportional drift chamber ; Fibre/foam sandwich radiator ; Xenon-based gas mixture ; Tracking ; Ionisation energy loss ; dE/dx ; TR ; Electron-pion identification ; Neural network ; Trigger01 natural sciencesParticle identificationdesign [detector]ALICEDetectors and Experimental Techniquesmomentum resolutionNuclear Experimentphysics.ins-detInstrumentationPhysicsPROTOTYPESLarge Hadron Collidertransition radiation detector; multi-wire proportional drift chamber;; fibre/foam sandwich radiator; Xenon-based gas mixture; tracking;; Ionisation energy loss; dE/dx; TR; electron-pion identification; Neural; network; trigger; COLLIDING BEAM EXPERIMENT; ELECTRON IDENTIFICATION; DRIFT CHAMBERS; TRD; PROTOTYPES; ENERGY-LOSS; GEV/C; COLLISIONS; PIONStrack data analysisTrackingPIONSDetectorVDP::Kjerne- og elementærpartikkelfysikk: 431Instrumentation and Detectors (physics.ins-det)trackingtransition radiation detector:Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 [VDP]ddc:PRIRODNE ZNANOSTI. Fizika.Xenon-based gas mixtureTransition radiation detector:Nuclear and elementary particle physics: 431 [VDP]VDP::Nuclear and elementary particle physics: 431GEV/Cmulti-wire proportional drift chamberperformanceParticle physicsNuclear and High Energy PhysicsCOLLISIONSelectron-pion identificationneural networkInstrumentationFOS: Physical sciencesTransition radiation detector; Multi-wire proportional drift chamber; Fibre/foam sandwich radiator; Xenon-based gas mixture; Tracking; Ionisation energy loss; dE/dx; TR; Electron-pion identification; Neural network; Trigger114 Physical sciencesMomentumNuclear physicsionisation energy loss0103 physical sciencesdE/dxDRIFT CHAMBERSdE/dx Electron-pion identification Fibre/foam sandwich radiator Ionisation energy loss Multi-wire proportional drift chamber Neural network TR Tracking Transition radiation detector Trigger Xenon-based gas mixture Nuclear and High Energy Physics Instrumentation.ddc:530[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det]seuranta010306 general physicsdetector: designNuclear and High Energy PhysicNeuralCOLLIDING BEAM EXPERIMENTTRD PROTOTYPESelectron: particle identificationta114010308 nuclear & particles physics:Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 [VDP]fibre/foam sandwich radiatortriggercalibrationNATURAL SCIENCES. Physics.Neural networkdE/dx; Electron-pion identification; Fibre/foam sandwich radiator; Ionisation energy loss; Multi-wire proportional drift chamber; Neural network; TR; Tracking; Transition radiation detector; Trigger; Xenon-based gas mixtureTriggerdE/dx; Electron-pion identification; Fibre/foam sandwich radiator; Ionisation energy loss; Multi-wire proportional drift chamber; Neural network; TR; Tracking; Transition radiation detector; Trigger; Xenon-based gas mixture; Nuclear and High Energy Physics; InstrumentationnetworkELECTRON IDENTIFICATIONTRDHigh Energy Physics::ExperimentALICE (propellant)ENERGY-LOSSNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
researchProduct

Searches for transverse momentum dependent flow vector fluctuations in Pb-Pb and p-Pb collisions at the LHC

2017

The measurement of azimuthal correlations of charged particles is presented for Pb-Pb collisions at $\sqrt{s_{\rm NN}}=$ 2.76 TeV and p-Pb collisions at $\sqrt{s_{\rm NN}}=$ 5.02 TeV with the ALICE detector at the CERN Large Hadron Collider. These correlations are measured for the second, third and fourth order flow vector in the pseudorapidity region $|��|<0.8$ as a function of centrality and transverse momentum $p_{\rm T}$ using two observables, to search for evidence of $p_{\rm T}$-dependent flow vector fluctuations. For Pb-Pb collisions at 2.76 TeV, the measurements indicate that $p_{\rm T}$-dependent fluctuations are only present for the second order flow vector. Similar results hav…

HEAVY-ION COLLISIONSnucl-extransverse momentum dependenceCOLLABORATIONangular correlation [charged particle]High Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)ALICEmodel: hydrodynamicstransport theory[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear Experiment (nucl-ex)[ PHYS.NEXP ] Physics [physics]/Nuclear Experiment [nucl-ex]Nuclear ExperimentNuclear ExperimentMonte CarloHeavy Ion Experiments; RELATIVISTIC NUCLEAR COLLISIONS; HEAVY-ION COLLISIONS; QUARK-GLUON; PLASMA; COLLECTIVE FLOW; COLLABORATIONPLASMAfluctuation [geometry]flow: anisotropygeometry: fluctuationQUARK-GLUONCERN LHC CollHeavy Ion Experiments; Nuclear and High Energy PhysicsflowRELATIVISTIC NUCLEAR COLLISIONSHeavy Ion ExperimentQuark-Gluon PlasmaParticle Physics - Experiment2760 GeV/nucleon5020 GeV/nucleonNuclear and High Energy PhysicsCERN LabCOLLECTIVE FLOWFOS: Physical sciencestransverse momentum[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]vector [fluctuation]Heavy Ion Experimentsscattering [heavy ion][ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex]factorizationlcsh:Nuclear and particle physics. Atomic energy. Radioactivityddc:530hydrodynamics [model]Nuclear Physics - Experimentnumerical calculationsinitial stateleadHeavy Ion Experiments Nuclear and High Energy Physics.hep-exboundary conditionrapiditycorrelationviscositylcsh:QC770-798High Energy Physics::Experimentp nucleusentropy: densitycharged particle: angular correlationexperimental results
researchProduct

Inclusive quarkonium production at forward rapidity in pp collisions at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usep…

2016

We report on the inclusive production cross sections of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{J}/\psi }$$\end{document}J/ψ, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\psi (\mathrm{2S})}$$\end{document}ψ(2S), \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepac…

Regular Article - Experimental PhysicsThe European Physical Journal. C, Particles and Fields
researchProduct

First measurement of the |t|-dependence of coherent J/ψ photonuclear production

2021

The first measurement of the dependence on $|t|$, the square of the momentum transferred between the incoming and outgoing target nucleus, of coherent J/ψ photoproduction is presented. The data were measured with the ALICE detector in ultra-peripheral Pb-Pb collisions at a centre-of-mass energy per nucleon pair $\sqrt{s_{\rm NN}} = 5.02$ TeV with the J/$\psi$ produced in the central rapidity region $|y| < 0.8$, which corresponds to the small Bjorken-$x$ range $(0.3 − 1.4) \times 10 ^{−3}$. The measured $|t|$-dependence is not described by computations based only on the Pb nuclear form factor, while the photonuclear cross section is better reproduced by models including shadowing according t…

heavy ion: scatteringnucleon: pairVDP::Matematikk og Naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431nucl-ex01 natural sciencesSquare (algebra)ALICEJ/psi(3100): photoproduction[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear ExperimentQuantum chromodynamicsPhysicsPhysicsForm factor (quantum field theory)ultra-peripheral collisionsdependence [impact parameter]J/psi ALICE Pb-Pb collisionsBalitsky-Kovchegov equationQuarkoniumddc:3. Good healthPHOTOPRODUCTIONshadowingNucleonParticle Physics - ExperimentPB-PB COLLISIONSNuclear and High Energy PhysicsQC1-999nucleus: form factor[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]MomentumNuclear physicsPHYSICSCross section (physics)heavy-ion collisions ultra-peripheral collisions quarkoniaphotoproduction [J/psi(3100)]scattering [heavy ion]0103 physical sciencesNuclear Physics - Experimentddc:530Rapidity5020 GeV-cms/nucleonHeavy Ion experiments010306 general physicsimpact parameter: dependencehep-ex010308 nuclear & particles physicsnucleus: targetpair [nucleon]photonuclear productionheavy-ion collisionsquarkoniaform factor [nucleus]PB-PB COLLISIONS; PHOTOPRODUCTION; PHYSICStarget [nucleus]J/PsicoherenceJ/psi(3100): photoproduction ; impact parameter: dependence ; nucleus: form factor ; nucleus: target ; nucleon: pair ; heavy ion: scattering ; coherence ; Balitsky-Kovchegov equation ; shadowing ; rapidity ; ALICE ; experimental results ; 5020 GeV-cms/nucleonrapidityphotonuclear production J/Psi Pb-Pb collisionsHigh Energy Physics::Experimentexperimental results
researchProduct

Dielectron production in proton-proton and proton-lead collisions at √sNN=5.02TeV

2020

The first measurements of dielectron production at midrapidity (|ηe| &lt; 0.8) in proton–proton and proton–lead collisions at √sNN = 5.02 TeV at the LHC are presented. The dielectron cross section is measured with the ALICE detector as a function of the invariant mass mee and the pair transverse momentum pT, ee in the ranges mee &lt; 3.5 GeV/c2 and pT, ee &lt; 8 GeV/c, in both collision systems. In proton–proton collisions, the charm and beauty cross sections are determined at midrapidity from a fit to the data with two different event generators. This complements the existing dielectron measurements performed at √s = 7 and 13 TeV. The slope of the √s dependence of the three measurements is…

Nuclear and High Energy Physics:Kjerne- og elementærpartikkelfysikk: 431 [VDP]ProtonHadronNuclear Theorydielectrondielectron production01 natural sciences7. Clean energyNuclear physicshadron-ion interactionshadron-hadron collisions; dielectron production;Ionic Collisionsdielectron cross sectiondielectron nuclear modification factor0103 physical sciencesInvariant massDielectronCharm (quantum number)Dielectron; hadron-hadron interactions; hadron-ion interactionsPhysics::Atomic PhysicsIonic Collisions; Relativistic Heavy-ion Collisions; Quark-Gluon Plasma010306 general physicsNuclear ExperimentQuantum chromodynamicsPhysicsLarge Hadron Collider010308 nuclear & particles physicsPhysicsVDP::Kjerne- og elementærpartikkelfysikk: 431hadron-hadron interactionNuclear matterhadron-hadron collisionsNATURAL SCIENCES. Physics.ALICE LHC proton-lead collisions proton-proton collisionsPRIRODNE ZNANOSTI. Fizika.:Nuclear and elementary particle physics: 431 [VDP]VDP::Nuclear and elementary particle physics: 431dielectron ; LHC ; dielectron cross section ; dielectron nuclear modification factorQuark–gluon plasmaQuark-Gluon PlasmaHigh Energy Physics::ExperimentLHChadron-hadron interactionsRelativistic Heavy-ion Collisions
researchProduct

Measurement of pion, kaon and proton production in proton–proton collisions at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym…

2015

The measurement of primary \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pi ^{\pm }$$\end{document}π±, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$K^{\pm }$$\end{document}K±, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrs…

Regular Article - Experimental PhysicsThe European Physical Journal. C, Particles and Fields
researchProduct

Production of K\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy}…

2016

The production of K\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{*}$$\end{document}∗(892)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^{0}$$\end{document}0 and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage…

Regular Article - Experimental PhysicsThe European Physical Journal. C, Particles and Fields
researchProduct

Measurement of quarkonium production at forward rapidity in \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfo…

2014

The inclusive production cross sections at forward rapidity of \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathrm{J}/\psi }$$\end{document}J/ψ, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\psi (\mathrm{2S})}$$\end{document}ψ(2S), \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} …

Regular Article - Experimental PhysicsThe European Physical Journal. C, Particles and Fields
researchProduct

Centrality dependence of charged jet production in p–Pb collisions at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepac…

2016

Measurements of charged jet production as a function of centrality are presented for  p–Pb  collisions recorded at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sqrt{s_\mathrm {NN}}= 5.02$$\end{document}sNN=5.02 TeV with the ALICE detector. Centrality classes are determined via the energy deposit in neutron calorimeters at zero degree, close to the beam direction, to minimise dynamical biases of the selection. The corresponding number of participants or binary nucleon–nucleon collisions is determined based on…

Regular Article - Theoretical PhysicsThe European Physical Journal. C, Particles and Fields
researchProduct

Energy dependence of the transverse momentum distributions of charged particles in pp collisions measured by ALICE

2013

Differential cross sections of charged particles in inelastic pp collisions as a function of $p_{\rm T}$ have been measured at $\sqrt{s}=$ 0.9, 2.76 and 7 TeV at the LHC. The $p_{\rm T}$ spectra are compared to NLO-pQCD calculations. Though the differential cross section for an individual $\sqrt{s}$ cannot be described by NLO-pQCD, the relative increase of cross section with $\sqrt{s}$ is in agreement with NLO-pQCD. Based on these measurements and observations, procedures are discussed to construct pp reference spectra at $\sqrt{s} =$ 2.76 and 5.02 TeV up to $p_{\rm T}$ = 50 GeV/$c$ as required for the calculation of the nuclear modification factor in nucleus-nucleus and proton-nucleus coll…

:Kjerne- og elementærpartikkelfysikk: 431 [VDP]Physics and Astronomy (miscellaneous)heavy ion collisionsNuclear Theory01 natural sciences7. Clean energySpectral lineHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)pp collisionALICEpp collisions; transverse momentum; ALICE[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear Experiment (nucl-ex)transverse momentum distributionNuclear ExperimentNuclear ExperimentPhysicsLarge Hadron Collidertransverse momentum; pp; ALICE; charged particlesPhysicsCharged particle3. Good health:Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 [VDP]:Nuclear and elementary particle physics: 431 [VDP]Transverse momentumLhcDiffractionpp collisionsParticle Physics - ExperimentRegular Article - Experimental PhysicsVDP::Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431particle productionFOS: Physical sciences[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]transverse momentumtransverse momentum distribution; PP COLLISIONSNuclear physicsRoot-S(Nn)=2.76 TevCross section (physics)0103 physical sciencesNuclear Physics - ExperimentPb-Pb Collisions010306 general physicsEngineering (miscellaneous)SuppressionALICE experiment; particle production; heavy ion collisionsVDP::Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyTransverse momentum distributions:Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 [VDP]ALICE experimentFunction (mathematics)Proton-Proton Collisionsp-p collisionHigh Energy Physics::ExperimentALICE (propellant)Energy (signal processing)
researchProduct