0000000001249170

AUTHOR

W. J. Burger

showing 7 related works from this author

Transverse momentum distributions for exclusive $\varrho^{0}$ muoproduction

1992

We have studied transverse momentum distributions for exclusive rho(0) muoproduction on protons and heavier nuclei at 2 < Q2 < 25 GeV2. The Q2 dependence of the slopes of the p(t)2 and t' distributions is discussed. The influence of the non-exclusive background is investigated. The p(t)2-slope for exclusive events is 4.3 +/- 0.6 +/- 0.7 GeV-2 at large Q2. The p(t)2 spectra are much softer than inclusive p(t)2 spectra of leading hadrons produced in deep inelastic scattering.

forward spectrometer: experimental resultsPhysics and Astronomy (miscellaneous)Nuclear Theorymuon nucleus: nuclear reactionchemistry.chemical_elementElementary particlemuon deuteron: nuclear reaction530Nuclear physicsmass spectrum: two-pionmomentum transfer: slopespectrum: transverse momentumField theory (psychology)Quantum field theoryNuclear Experimentrho(770)0: electroproductionEngineering (miscellaneous)muon p: exclusive reactionPhysicspomeron: exchangecalciumtwo-pion: mass spectrumbackgroundelectroproduction: rho(770)0carbon200 GeVCERN SPSDeep inelastic scatteringParticle accelerationexchange: pomeronchemistrytransverse momentum: spectrumQuantum electrodynamicsTransverse momentumHigh Energy Physics::ExperimentCarbonParticle Physics - Experimentmuon p --> rho(770)0 nucleon
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Quark and gluon distributions and $\alpha_{s}$ from nucleon structure functions at low $x$

1993

Abstract The Q2 dependence of the structure functions F2p and F2d recently measured by the NMC is compared with the predictions of perturbative QCD at next-to-leading order. Good agreement is observed, leading to accurate determinations of the quark and gluon distributions in the range 0.008 ⩽ × ⩽ 0.5. The strong coupling constant is measured from the low x data; the result agrees with previous determinations.

QuarkNuclear and High Energy PhysicsParticle physicsHigh Energy Physics::Latticedeep inelastic scattering: muon deuteronmuon deuteron: deep inelastic scatteringPARTON DENSITIESJet (particle physics)530CROSS-SECTIONSNuclear physicsnumerical calculations: interpretation of experimentsstrong interaction: coupling constant90: 280 GeVDEEP INELASTIC-SCATTERING; LEADING ORDER; QUANTUM CHROMODYNAMICS; PERTURBATION-THEORY; PARTON DENSITIES; CROSS-SECTIONS; FREEDOM; MSBAR; JET; NMCdeep inelastic scattering: muon pp: structure functionNMCCoupling constantQuantum chromodynamicsPhysicsQUANTUM CHROMODYNAMICSLEADING ORDERHigh Energy Physics::Phenomenologydeuteron: structure functiongluon: momentum spectrumperturbation theory: higher-orderPerturbative QCDDeep inelastic scatteringquark: momentum spectrumFREEDOMGluondependence: momentum transferJETMSBARmuon p: deep inelastic scatteringPERTURBATION-THEORYDEEP INELASTIC-SCATTERINGHigh Energy Physics::Experimentcoupling constant: strong interactionNucleonParticle Physics - Experiment
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Measurements of $R^{d}-R^{p}$ and $R^{Ca}-R^{C}$ in deep inelastic muon scattering

1992

Results are presented on the difference in R, the ratio of longitudinally to transversely polarised virtual photon absorption cross sections, for the deuteron and the proton. They are obtained by c ...

Nuclear and High Energy PhysicsProtonmuon nucleus: deep inelastic scatteringNuclear Theorypolarization: longitudinaldeep inelastic scattering: muon deuteronVirtual particlecross section: ratiophoton: absorptionElementary particlemuon deuteron: deep inelastic scattering530Nuclear physicsabsorption: photondeep inelastic scattering: muon ppolarization: transverseHIGH STATISTICS MEASUREMENT; R=SIGMA-L/SIGMA-T; HIGH Q2Nuclear ExperimentAbsorption (electromagnetic radiation)deep inelastic scattering: muon nucleus90: 200: 280 GeVPhysicsHIGH STATISTICS MEASUREMENTMuoncalciumScatteringcarbonstructure function: ratioR=SIGMA-L/SIGMA-TCERN SPSlongitudinal: polarizationParticle scatteringDeuteriummuon p: deep inelastic scatteringHIGH Q2Physics::Accelerator Physicstransverse: polarizationAtomic physicsParticle Physics - Experimentexperimental results
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Exclusive ϱ0 and φ muoproduction at large Q2

1994

Abstract Exclusive ϱ 0 and φ muoproduction on deuterium, carbon and calcium has been studied in the kinematic range 2 Q 2 2 and 40 Q 2 dependence of the cross sections, the transverse momentum distributions for the vector mesons, the decay angular distributions and, in the case of the ϱ 0 , nuclear effects. The data for 0 production are compatible with a diffractive mechanism. The distinct features of φ production are a smaller cross section and less steep p t 2 distributions than those for the 0 mesons.

PhysicsNuclear and High Energy PhysicsRange (particle radiation)Particle physicsMesonHADRONSMUON SCATTERINGTRANSVERSE-MOMENTUMPROTONQCD530Nuclear physicsCross section (physics)RATIOAngular distributionDeuteriumTransverse momentumDEEP INELASTIC-SCATTERING; MUON SCATTERING; TRANSVERSE-MOMENTUM; PROTON; HADRONS; RATIO; QCDDEEP INELASTIC-SCATTERINGNuclear Physics B
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Precision measurement of the structure function ratiosF 2 He /F 2 D ,F 2 C /F 2 D andF 2 Ca /F 2 D

1991

We present the structure function ratiosF2He/F2D,F2C/F2D andF2Ca/F2D measured in deep inelastic muon-nucleus scattering at an incident muon momentum of 200 GeV. The kinematic range 0.0035<x<0.65 and 0.5<Q2<90 GeV2 is covered. At lowx the three ratios are significantly smaller than unity and the size of the depletion grows with decreasingx and increasing mass numberA. At intermediatex the ratios show an enhancement of about 2% above unity for C/D and Ca/D, possibly less for He/D. There are indications of someQ2 dependence in the Ca/D data. The integrals of the structure function differencesF2A−F2D are discussed.

PhysicsMomentum (technical analysis)MuonPhysics and Astronomy (miscellaneous)ScatteringStructure functionchemistry.chemical_elementElementary particle530Particle accelerationchemistryAtomic physicsEngineering (miscellaneous)Particle Physics - ExperimentHeliumZeitschrift f�r Physik C Particles and Fields
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Precision measurement of structure function ratios for $^{6}$Li, $^{12}$C and $^{40}$Ca

1992

The structure function ratiosF2C/F2Li,F2Ca/F2Li andF2Ca/F2C were measured in deep inelastic muonnucleus scattering at an incident muon energy of 90 GeV, covering the kinematic range 0.0085<x<0.6 and 0.8<Q2<17GeV2. The sensitivity of the nuclear structure functions to the size and mean density of the target nucleus is discussed.

PhysicsRange (particle radiation)MuonPhysics and Astronomy (miscellaneous)ScatteringNuclear structureElementary particleNuclear physicsmedicine.anatomical_structureDeuteriummedicineAtomic physicsEngineering (miscellaneous)NucleusElectron scatteringParticle Physics - Experiment
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Search for neutral MSSM Higgs bosons at LEP

2006

The four LEP collaborations, ALEPH, DELPHI, L3 and OPAL, have searched for the neutral Higgs bosons which are predicted by the Minimal Supersymmetric Standard Model (MSSM). The data of the four collaborations are statistically combined and examined for their consistency with the background hypothesis and with a possible Higgs boson signal. The combined LEP data show no significant excess of events which would indicate the production of Higgs bosons. The search results are used to set upper bounds on the cross-sections of various Higgs-like event topologies. The results are interpreted within the MSSM in a number of "benchmark" models, including CP-conserving and CP-violating scenarios. Thes…

AlephPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; ALEPH; DELPHI; L3; OPALPhysics and Astronomy (miscellaneous)Parameter space01 natural sciencesOPAL DETECTORHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Event (probability theory)BosonPhysicsEXPLICIT CP VIOLATIONROOT-S=189 GEVOPALFLAVOR INDEPENDENT SEARCHParticle physics - ExperimentPhysicsSettore FIS/01 - Fisica SperimentaleHiggs particle. search forSUPERGAUGE TRANSFORMATIONSALEPHLARGE ELECTRON POSITRON COLLIDERALEPH DELPHI L3 OPALSUPERSYMMETRIC STANDARD MODELROOT-SL3Higgs bosonPARTICLE PHYSICSParticle physicselectron positron. colliding beamselectron positron. annihilationFOS: Physical sciencessupersymmetric standard model;; explicit cp violation;; electric-dipole moment;; e(+)e(-) collisions;; root-s=189 gev;; opal detector;; root-s;; z(0) decays;; supergauge transformations;; radiative-correctionsHiggs particle. electroproductionddc:500.2-SUPERSYMMETRIC STANDARD MODEL; EXPLICIT CP VIOLATION; FLAVOR INDEPENDENT SEARCH; ELECTRIC-DIPOLE MOMENT; E(+)E(-) COLLISIONS; ROOT-S; ROOT-S=189 GEV; OPAL DETECTOR; Z(0) DECAYS; SUPERGAUGE TRANSFORMATIONSHiggs particleLEP colliderNext-to-Minimal Supersymmetric Standard ModelELECTRIC-DIPOLE MOMENTE(+)E(-) COLLISIONSConsistency (statistics)0103 physical sciencesddc:530High Energy Physics010306 general physicsEngineering (miscellaneous)DELPHIelectron positron010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyHiggs BosonLEPHIGGSHiggs boson standard modelZ(0) DECAYSExperimental High Energy PhysicsHigh Energy Physics::ExperimentHiggs Boson; LEP colliderMSSMMinimal Supersymmetric Standard ModelHiggs
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