Search results for " Anni"

showing 10 items of 847 documents

Limit on the production of a light vector gauge boson in $\phi $ mesondecays with the KLOE detector

2012

We present a new limit on the production of a light dark-force mediator with the KLOE detector at DAPHNE. This boson, called U, has been searched for in the decay phi --> eta U, U --> e+ e-, analyzing the decay eta --> pi0 pi0 pi0 in a data sample of 1.7 fb-1. No structures are observed in the e+e- invariant mass distribution over the background. This search is combined with a previous result obtained from the decay eta --> pi+ pi- pi0, increasing the sensitivity. We set an upper limit at 90% C.L. on the ratio between the U boson coupling constant and the fine structure constant of alpha'/alpha < 1.7x10^-5 for 30<M_U<400 MeV and alpha'/alpha < 8x10^-6 for the sub-region 50<M_U<210 MeV. This…

Dark forcesNuclear and High Energy PhysicsParticle physicsElectron–positron annihilationFOS: Physical sciences01 natural sciencesSettore FIS/04 - Fisica Nucleare e Subnuclearee(+)e(-) Collisions Dark forces Gauge vector bosonHigh Energy Physics - ExperimentNuclear physicsHigh Energy Physics - Experiment (hep-ex)e(+)e(-) Collisions0103 physical sciencesgauge vector bosonInvariant massNuclear Experiment010306 general physicsBosonPhysicsCoupling constantGauge boson$e^{+}e^{-}$ collisions010308 nuclear & particles physicsSettore FIS/01 - Fisica SperimentaleForm factor (quantum field theory)Vector meson dominancePhi mesondark forcesHigh Energy Physics::ExperimentGauge vector boson
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Study of high-multiplicity three-prong and five-prong τ decays at BABAR

2012

We present measurements of the branching fractions of three-prong and five-prong tau decay modes using a sample of 430 million tau lepton pairs, corresponding to an integrated luminosity of 468 fb(-1), collected with the BABAR detector at the PEP-II asymmetric-energy e_e storage rings at SLAC National Accelerator Laboratory. The tau(-) -> (3 pi)(-) eta nu(tau), tau(-) -> (3 pi)(-) omega nu(tau), and tau(-) f(1) (1285)nu(tau) branching fractions are presented, as well as a new limit on the branching fraction of the second-class current decay tau(-) -> pi(-) eta'(958)nu(tau). We search for the decay mode tau(-) -> K- eta'(958)nu(tau) and for five-prong decay modes with kaons, and place the fi…

Decays of taus; TausNuclear and High Energy PhysicsParticle physicsElectron–positron annihilationDecays of tausPACS: 13.35.Dx 14.60.FgHigh multiplicity01 natural sciencesTausNuclear physics0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Decays of tau010306 general physicsCurrent decayPhysics010308 nuclear & particles physicsBranching fractionLeptons (Física nuclear)Particle physicsHEPLeptons (Nuclear physics)BaBarHigh Energy Physics::ExperimentExperimentsFísica de partículesLepton
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Analytical O(αs) corrections to the beam frame double-spin density matrix elements of e+e−→tt¯

2016

We provide analytical results for the $O({\ensuremath{\alpha}}_{s})$ corrections to the double-spin density matrix elements in the reaction ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}t\overline{t}$. These concern the elements $ll$, $lt$, $ln$, $tt$, $tn$, and $nn$ of the double-spin density matrix elements where $l$, $t$, $n$ stand for longitudinal, transverse and normal orientations with respect to the beam frame spanned by the electron and the top quark momentum.

Density matrixPhysicsTop quark010308 nuclear & particles physicsElectron–positron annihilationHigh Energy Physics::PhenomenologyElectron01 natural sciencesMomentumMatrix (mathematics)Transverse plane0103 physical sciencesAtomic physics010306 general physicsBeam (structure)Physical Review D
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Use of positron annihilation measurements to detect the defect beneath worn surface of stainless steel 1.4301 (EN) under dry sliding condition

2012

Abstract Positron measurements were performed for detection of the subsurface zone in the stainless steel 1.4301 (EN) exposed to dry sliding. They revealed the defect profile induced by dry sliding which is extended inward the worn surface from 85 μm to 400 μm depending on the applied load during the tribo-test. This result was obtained using the positron techniques, while the microhardness profile exhibited shorter range of the microhardness depth profile, i.e., from 70 μm to 150 μm. However, at the depth of about 5 μm from the worn surface the sudden increase in the microhardness was observed. The complementary measurements of X-ray diffraction and SEM micrographs of the worn surface were…

DiffractionSem micrographsMaterials sciencePositronMechanics of MaterialsMetallurgyMaterials ChemistrySurfaces and InterfacesCondensed Matter PhysicsIndentation hardnessSurfaces Coatings and FilmsSliding wearPositron annihilationWear
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Tevatron Run II combination of the effective leptonic electroweak mixing angle

2018

The Ministry of Science and Innovation and the Consolider-Ingenio 2010 Program and the European Union community Marie Curie Fellowship Contract No. 302103.

Drell-Yan processsemianalytical programsPhysics and Astronomy (miscellaneous)FERMION PAIR PRODUCTIONUPGRADETevatronhadron-colliders01 natural sciencesHigh Energy Physics - ExperimentPhysics Particles & Fieldselectron: pair productionHigh Energy Physics - Experiment (hep-ex)MONTE-CARLOUNIVERSAL MONTE-CARLOELECTROMAGNETIC CALORIMETERDZERO[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]HADRON COLLIDERSangular distributionBatavia TEVATRON CollMonte CarloPhysicsscattering [anti-p p]gauge bosonPhysicsElectroweak interactionDrell–Yan processWeinberg anglespontaneous symmetry breaking [electroweak interaction]muon: pair productionPhysical Sciencesmixing angle [electroweak interaction]bosonPHOTOSmass: measured [W]asymmetryParticle physicsFOS: Physical sciencesSEMIANALYTICAL PROGRAMddc:500.2Astronomy & Astrophysicselectroweak interaction: spontaneous symmetry breaking114 Physical sciences530programmingW: mass: measuredStandard Modelanti-p p: colliding beams[ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex]hadroproduction [Z0]0103 physical sciencesanti-p p: scatteringddc:530High Energy Physicspair production [electron]pair production [muon]CALORIMETER010306 general physicsQED RADIATIVE-CORRECTIONSQed radiative-corrections; fermion pair production; universal; Monte Carlo; parton distributions; hadron-colliders; electromagnetic; calorimeter;semianalytical programs; E(+)E(-) annihilation; boson; production; D0 detectorGauge bosonBOSON PRODUCTIONMuonScience & Technologyelectroweak interaction: mixing angleAnti-p p: scattering | anti-p p: colliding beams | Z0: hadroproduction | Z0: leptonic decay | electroweak interaction: spontaneous symmetry breaking | electroweak interaction: mixing angle | muon: pair production | W: mass: measured | Weinberg angle | Batavia TEVATRON Coll | angular distribution | electron: pair production | Drell-Yan process | gauge boson | programming | asymmetry | CDF | DZERO | experimental resultsIDENTIFICATION010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyuniversalWeinberg angleZ0: hadroproductionQED RADIATIVE-CORRECTIONS; FERMION PAIR PRODUCTION; UNIVERSAL; MONTE-CARLO; PARTON DISTRIBUTIONS; HADRON COLLIDERS; ELECTROMAGNETIC; CALORIMETER; SEMIANALYTICAL PROGRAM; E(+)E(-) ANNIHILATION; BOSON; PRODUCTION; D0 DETECTORleptonic decay [Z0]E(+)E(-) ANNIHILATIONelectromagneticPARTON DISTRIBUTIONSExperimental High Energy PhysicsZ0: leptonic decayD0 DETECTORCDFHigh Energy Physics::Experimentproductioncolliding beams [anti-p p]Leptonexperimental results
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Sul settantesimo anniversario della Convenzione europea: fra successi e prospettive di alterazione del sistema

2020

In this paper it is submitted that an assessment of the functioning of the European system of protection of human rights lead to different results, depending on whether one considers the entire life of this system or the last twenty years (par. 1). Such an assessment is beyond any doubt positive in the first case, insofar as both the action of the States parties (progressive "jurisdictionalisation" of the protection system; extension to eastern Europe, ecc.) and the case law of the European Court (evolutive interpretation, ecc.) are concerned (par. 2). Different considerations are developed with regard to the last twenty years, despite the stipulation of Protocol 14, 15 and 16, and despite …

European System of Human Rights 70th Anniversary lights and shadowsSettore IUS/13 - Diritto Internazionale
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Observation of e + e − → ηψ(2S) at center-of-mass energies from 4.236 to 4.600 GeV

2021

Journal of high energy physics 2021(10), 177 (2021). doi:10.1007/JHEP10(2021)177

ExoticsNuclear and High Energy Physicsmeasured [channel cross section]e+-e− ExperimentsQuarkoniumannihilation [electron positron]QC770-798electron positron: annihilationetaParticle and resonance productionMeasure (mathematics)530Standard deviationNONuclear physicsSubatomär fysikCross section (physics)e+-e��� Experimentsenergy dependence: measured [cross section]Astronomi astrofysik och kosmologiNuclear and particle physics. Atomic energy. RadioactivitySubatomic PhysicsAstronomy Astrophysics and Cosmologyddc:530e+-e− Experiments Exotics Particle and resonance production Quarkoniumpsi(3685)PhysicsBESe(+)-e(-) ExperimentsDetectorstatistical [error]electron positron --> eta psi(3685)e +-e − Experimentselectron positron: colliding beamsBeijing Stor4.236-4.600 GeV-cmsCollisionerror: statisticalYield (chemistry)e-e Experimentselectron positron --&gt; eta psi(3685)colliding beams [electron positron]High Energy Physics::ExperimentCenter of masscross section: energy dependence: measuredchannel cross section: measuredStorage ringexperimental results
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GUTTUSO E LEVI: STORIA D'ARTE E DI AMICIZIA

2007

GUTTUSO LEVI PITTURA ANNI TRENTASettore L-ART/03 - Storia Dell'Arte Contemporanea
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Measurement of $\Delta^{++}$(1232) production in hadronic Z decays

1995

A measurement of the \Delta^{++}(1232) inclusive production in hadronic decays of the Z at LEP is presented, based on 1.3 million hadronic events collected~ by the DELPHI~ detector in the 1994 LEP running~ period. The DELPHI ring imaging Cherenkov counters are used for identifying hadrons. The average \Delta^{++}(1232) multiplicity per hadronic event is 0.079 \pm 0.015 which is more than a factor of two below the JETSET, HERWIG and UCLA model predictions. It agrees with a recently proposed universal mass dependence of particle production rates in e^{+}e^- annihilations.

Hadronic decayNuclear and High Energy PhysicsParticle physicsE+E ANNIHILATIONSe+e- annihilationCherenkov detectorElectron–positron annihilationDELPHI; hadronic decay; Cherenkov detector; e+e- annihilationHadron01 natural sciencesPartícules (Física nuclear)law.inventionNuclear physicslaw0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Multiplicity (chemistry)010306 general physicsCherenkov radiationhadronic decayDELPHIPhysics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyLARGE ELECTRON POSITRON COLLIDERPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearHigh Energy Physics::ExperimentParticle Physics - ExperimentCherenkov detector
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Measurement of the Branching Fractions of ExclusiveB¯→D(*)(π)l−ν¯lDecays in Events with a Fully ReconstructedBMeson

2008

We report a measurement of the branching fractions for _B-->D(*)(pi)l- _nu(l) decays based on 341.1 fb(-1) of data collected at the Upsilon(4S) resonance with the BABAR detector at the SLAC PEP-II e+ e- storage rings. Events are tagged by fully reconstructing one of the B mesons in a hadronic decay mode. We obtain B(B- -->D(0)l-_nu(l)=(2.33+/-0.09(stat)+/-0.09(syst)%, B(B- -->D(*0)l-_nu(l)=(5.83+/-0.15(stat) +/-0.30(syst) %, B(_B(0)-->D+l-_nu(l)=(2.21+/-0.11(stat) +/-0.12(syst)%, B(_B(0)-->D(*)l-_nu(l)=(5.49+/-0.16(stat)+/-0.25(syst)%, B(B- -->D+pi-l-_nu(l)=(0.42+/-0.06(stat)+/-0.03(syst)%, B(B- -->D(*)+pi-l-_nu(l)=(0.59+/-0.05(stat)+/-0.04(syst)%, B(_B(0)-->D(0)pi+l-_nu(l)=(0.43+/-0.08(sta…

Hadronic decayNuclear physicsPhysics010308 nuclear & particles physicsStereochemistryElectron–positron annihilation0103 physical sciencesGeneral Physics and AstronomyB meson010306 general physics01 natural sciencesPhysical Review Letters
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