0000000001152230

AUTHOR

N. Degroot

showing 3 related works from this author

Classification of the hadronic decays of the Z$^0$ into b and c quark pairs using a neural network

1992

A classifier based on a feed-forward neural network has been used for separating a sample of about 123 500 selected hadronic decays of the Z 0 , collected by DELPHI during 1991, into three classes according to the flavour of the original quark pair: u u +d d +s s (unresolved), c c and b b . The classification has been used to compute the partial widths of the Z 0 into b and c quark pairs. This gave Γ c c /Γ h = 0.151 ± 0.008 ( stat. ) ± 0.041 ( syst. ) , Γ b b /Γ h = 0.232±0.005 ( stat. )±0.017 ( syst. ) .

QuarkNuclear and High Energy PhysicsParticle physicsLUND MONTE-CARLO; HEAVY FLAVOR PRODUCTION; JET FRAGMENTATION; PHYSICS; BOSONHEAVY FLAVOR PRODUCTIONLUND MONTE-CARLOElectron–positron annihilationFlavourHadronMathematicsofComputing_GENERALComputer Science::Digital Libraries01 natural sciencesJET FRAGMENTATIONCharm quarkPHYSICS0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsPhysicsArtificial neural network010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyTheoryofComputation_GENERALBOSONMathMLComputer Science::Mathematical SoftwareHigh Energy Physics::ExperimentFísica nuclearClassifier (UML)Particle Physics - Experiment
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A Measurement of Sin2-theta-w From the Charge Asymmetry of Hadronic Events At the Z0 Peak

1992

Abstract View references (24)The weak mixing angle has been measured from the charge asymmetry of hadronic events with two different approaches using the DELPHI detector at LEP. Both methods are based on a momentum-weighted charge sum to determine the jet charge in both event hemispheres. In a data sample of 247 300 multihadronic Z0 decays a charge asymmetry of 〈QF〉 - 〈QB〉 = -0.0076±0.0012(stat.)±0.0005(exp. syst.)±0.0014(frag.) and a raw forward-backward asymmetry of Araw FB = -0.0109±0.0020(stat.)±0.0010(exp. syst.)±0.0017(frag.) have been measured. This result corresponds to a value of sinθeff=0.2345±0.0030(exp.)±0.0027(frag.) ,sin2θMS=0.2341±0.0030(exp.)±0. 0027(frag.) and to sin2θW=1-m…

Nuclear and High Energy PhysicsParticle physicsE+E ANNIHILATIONLUND MONTE-CARLOElectron–positron annihilationmedia_common.quotation_subjectHadronJet (particle physics)collective information systems01 natural sciencesAsymmetryJET FRAGMENTATIONNuclear physicsPHYSICS0103 physical sciencespersonal information system[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]LUND MONTE-CARLO; E+E ANNIHILATION; JET FRAGMENTATION; Z-DECAYS; PHYSICS010306 general physicsZ-DECAYSmedia_commonPhysicsRange (particle radiation)010308 nuclear & particles physicsWeinberg angleCharge (physics)information scienceQuadratic Gauss suminformation praticesPhysique des particules élémentairesHigh Energy Physics::ExperimentFísica nuclearParticle Physics - Experiment
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Charged particle multiplicity distributions in restricted rapidity intervals in Z0 hadronic decays.

1991

The multiplicity distributions of charged particles in restricted rapidity intervals in Z0 hadronic decays measured by the DELPHI detector are presented. The data reveal a shoulder structure, best visible for intervals of intermediate size, i.e. for rapidity limits around ±1.5. The whole set of distributions including the shoulder structure is reproduced by the Lund Parton Shower model. The structure is found to be due to important contributions from 3-and 4-jet events with a hard gluon jet. A different model, based on the concept of independently produced groups of particles, "clans", fluctuating both in number per event and particle content per clan, has also been used to analyse the pres…

COLLISIONSParticle physicsE+E ANNIHILATIONPhysics and Astronomy (miscellaneous)LUND MONTE-CARLOElectron–positron annihilationHadronElementary particlePETRA ENERGIES01 natural sciences250 GEV/CNuclear physicsDEPENDENCE0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RapidityNuclear Experiment010306 general physicsParton showerEngineering (miscellaneous)LUND MONTE-CARLO; JET PRODUCTION-RATES; E+E ANNIHILATION; 250 GEV/C; PETRA ENERGIES; COLLISIONS; DEPENDENCE; FRAGMENTATION; QCD; RESONANCEPhysics010308 nuclear & particles physicsJET PRODUCTION-RATESMultiplicity (mathematics)RESONANCEQCDCharged particleGluonPhysique des particules élémentairesHigh Energy Physics::ExperimentFRAGMENTATIONParticle Physics - Experiment
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