0000000000405099

AUTHOR

Andreas Hocker

showing 6 related works from this author

Four-jet final state production in e+e- collisions at centre-of-mass energies of 130 and 136 GeV

1996

The four-jet final state is analyzed to search for hadronic decays of pair-produced heavy particles. The analysis uses the ALEPH data collected at LEP in November 1995 at centre-of-mass energies of 130 and 136 GeV, corresponding to a total integrated luminosity of 5.7 pb(-1). An excess of four-jet events is observed with respect to the standard model predictions. In addition, these events exhibit an enhancement in the sum of the two di-jet masses around 105 GeV/c(2). The properties of these events are studied and compared to the expectations from standard processes and to pair production hypotheses. RI ANTONELLI, ANTONELLA/C-6238-2011; Passalacqua, Luca/F-5127-2011; Murtas, Fabrizio/B-5729-…

PhysicsParticle physicsLuminosity (scattering theory)Physics and Astronomy (miscellaneous)Electron–positron annihilationPhysicsAstrophysics::High Energy Astrophysical PhenomenaHadronSettore FIS/01 - Fisica SperimentaleJet (particle physics)e+e- experimentStandard ModelALEPH ExperimentNuclear physicsPair productionHiggs bosonHigh Energy Physics::ExperimentALEPH experimentParticle Physics - Experiment
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Studies of QCD in ${\rm e^+ e^-}\to $ hadrons at $E_{\rm cm} = 130$ and 136 GeV

1997

Studies of QCD in $\mbox{e}^+\mbox{e}^- \rightarrow$ Hadrons at $E_{cm} = $} 130 and 136 GeV The ALEPH Collaboration An analysis of the properties of hadronic final states produced in electron-positron annihilation at centre-of-mass energies of 130 and 136 GeV is presented. The measurements are based on a data sample of 5.7 $\mbox{pb}^{-1}$ collected in November 1995 with the \Aleph detector at LEP. Inclusive charged particle distributions, jet rates and event-shape distributions are measured and the results are compared with the predictions of QCD-based models. From the measured distributions quantities are determined for which the dependence on the centre-of-mass energy can be predicted b…

PhysicsQuantum chromodynamicsAlephParticle physicsAnnihilationPhysics and Astronomy (miscellaneous)Electron–positron annihilationHigh Energy Physics::PhenomenologyHadronCharged particleNuclear physicsStrong couplingHigh Energy Physics::ExperimentMultiplicity (chemistry)Particle Physics - ExperimentZeitschrift f�r Physik C Particles and Fields
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Branching Ratios and Spectral Functions of $\tau$ Decays: final ALEPH measurements and physics implications

2005

The full LEP-1 data set collected with the ALEPH detector at the $Z$ pole during 1991-1995 is analysed in order to measure the $\tau$ decay branching fractions. Extensive systematic studies are performed, in order to match the large statistics of the data sample corresponding to over 300 000 measured and identified $\tau$ decays. Branching fractions are obtained for the two leptonic channels and eleven hadronic channels defined by their respective numbers of charged particles and $\pi^0$'s. Using previously published ALEPH results on final states with charged and neutral kaons, corrections are applied to the hadronic channels to derive branching ratios for exclusive final states without kao…

tau; branching fractions; Z poleParticle physicsbranching fractionElectron–positron annihilationHadronFOS: Physical sciencesGeneral Physics and AstronomyStrangeness01 natural sciencesAsymptotic freedomhadronicHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)tau decay; PION FORM-FACTOR; ELECTROWEAK RADIATIVE-CORRECTIONSquantum chromodynamictau decay0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]tau010306 general physicsMinimal subtraction schemeQuantum chromodynamicsPhysics010308 nuclear & particles physicsZ poleHigh Energy Physics::PhenomenologyCharged particle3. Good healthsum rulebranching fractionsIsospinHigh Energy Physics::ExperimentELECTROWEAK RADIATIVE-CORRECTIONSParticle Physics - ExperimentPION FORM-FACTOR
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Search for sleptons in e+e− collisions at centre-of-mass energies of 161 GeV and 172 GeV

1997

The data recorded by the ALEPH experiment at LEP at centre-of-mass energies of 161 GeV and 172 GeV were analysed to search for sleptons, the supersymmetric partners of leptons. No evidence for the production of these particles was found. The number of candidates observed is consistent with the background expected from four-fermion processes and gammagamma-interactions. Improved mass limits at 95% C.L. are reported.

Nuclear and High Energy PhysicsParticle physicsAlephElectron–positron annihilationMonte Carlo methodFOS: Physical sciencesALEPH Experiment; LEP; sleptons01 natural sciencesLower limitHigh Energy Physics - ExperimentNuclear physicsALEPH ExperimentHigh Energy Physics - Experiment (hep-ex)0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsALEPH experimentPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologySupersymmetryLEPPair productionHigh Energy Physics::ExperimentParticle Physics - ExperimentsleptonsLepton
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Strange quark mass from the invariant mass distribution of Cabibbo-suppressed tau decays

2001

8 páginas, 4 figuras, 4 tablas.-- arXiv:hep-ph/0105253v1

QuarkPhysicsStrange quarkAlephParticle physicsPhysics and Astronomy (miscellaneous)High Energy Physics::PhenomenologyNuclear TheoryHadronFOS: Physical sciencesFísicaHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Distribution (mathematics)High Energy Physics::ExperimentMass scaleInvariant massSpectral functionNuclear ExperimentEngineering (miscellaneous)
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Strange quark mass from τ decays

2001

7 páginas, 3 figuras, 3 tablas.-- Comunicación presentada en el 6º International Workshop on Tau Lepton Physics (Tau00) celebrado del 18 al 21 de Septiembre de 2000 en Victoria (Canada).

Nuclear physicsPhysicsNuclear and High Energy PhysicsStrange quarkAlephParticle physicsScale (ratio)Nuclear TheoryHadronHigh Energy Physics::ExperimentSpectral functionNuclear ExperimentAtomic and Molecular Physics and Optics
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