Search results for "Particle physics"

showing 10 items of 6826 documents

Exotic states in the S=1 N-pi-K system and low-lying 1/2+ S=-1 resonances

2010

In this manuscript we discuss about our study of the $N \pi \bar{K}$ and the NπK systems made by solving the Faddeev equations with the two-body t-matrices obtained by solving the Bethe-Salpeter equations with the potentials obtained from chiral dynamics. In the strangeness = -1 case, we found that all the Λ and Σ resonances listed by the particle data group, with spin-parity 1/2+ , in the 1550-1800 MeV region get generated due to the involved three-body dynamics. This motivated us to study the strangeness =1 three-body system, i.e., NπK , where we did not find any evidence for the Θ + (1542) but found a broad bump around 1700 MeV which has a κ (800)N structure.

Nuclear physicsPhysicsFaddeev equationsParticle physicsBethe–Salpeter equationPhysicsQC1-999Structure (category theory)Particle Data GroupStrangenessThree-body problemBar (unit)S-matrixEPJ Web of Conferences
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Production and decay of charmed mesons at the Z resonance

1991

Abstract In a sample of 190 000 hadronic Z decays, three signals of charm production are observed: two from the exclusive decays D ° → K − π + and D ∗+ → D °π + → K − π + π + and one in the transverse-momentum distribution of soft hadrons relative to the nearest jet. The features of these signals are in good agreement with expectations based on the standard model and previous measurements of the branching fractions. The number of D ∗± → K ± π ± π ± per hadronic decay of the Z is measured to be (5.11±0.34) × 10 −3 , and the branching ratio B(D 0 → K − π + ) is (3.62 ± 0.34 ± 0.44)%. Charm hadronization has been studied. The average fraction of the beam energy carried by the D ∗ meson is foun…

Nuclear physicsPhysicsHadronic decayNuclear and High Energy PhysicsParticle physicsMesonBranching fractionElectron–positron annihilationHadronBeam energyParticle Physics - ExperimentHadronization
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10.8 Conclusion

2008

Nuclear physicsPhysicsHiggs fieldParticle physicsBaryon asymmetryPontecorvo–Maki–Nakagawa–Sakata matrixCP violationCosmology
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Delayed Pion Spectroscopy of Hypernuclei

2014

New possibilities of hypernuclear studies at modern electron accelerators based on recently developed radio frequency photomultiplier tubes are discussed.

Nuclear physicsPhysicsHistoryPhotomultiplierParticle physicsPionElectronRadio frequencySpectroscopyComputer Science ApplicationsEducationJournal of Physics: Conference Series
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Measurement of the Ratio of theνμCharged-Current Single-Pion Production to Quasielastic Scattering with a 0.8 GeV Neutrino Beam on Mineral Oil

2009

Charged current single pion production (CC{pi}{sup +}) and charged current quasi-elastic scattering (CCQE) are the most abundant interaction types for neutrinos at energies around 1 GeV, a region of great interest to oscillation experiments. The cross-sections for these processes, however, are not well understood in this energy range. This dissertation presents a measurement of the ratio of CC{pi}{sup +} to CCQE cross-sections for muon neutrinos on mineral oil (CH{sub 2}) in the MiniBooNE experiment. The measurement is presented here both with and without corrections for hadronic re-interactions in the target nucleus and is given as a function of neutrino energy in the range 0.4 GeV < E{sub…

Nuclear physicsPhysicsMiniBooNEParticle physicsMuonPionHadronGeneral Physics and AstronomyHigh Energy Physics::ExperimentNeutrinoEnergy sourceCharged currentLeptonPhysical Review Letters
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Charged charmed particle lifetime

1984

Abstract We present the lifetime values obtained for D ± and Λ c + , photoproduced in nuclear emulsion in the WA58 experiment. In photohadronic interactions, pairs of charmed particles are produced. Out of 20 charged charmed particles used for lifetime evaluation, 17 have their charmed partner seen emulsion, being then essentially free from any background. The values of the lifetime are τ D ± = (3.91 −1.25 +2.35 ) × 10 −13 s, τ Λ c + = (2.22 −0.75 +1.34 ) × 10 −13 s.

Nuclear physicsPhysicsNuclear and High Energy Physics010308 nuclear & particles physics0103 physical sciencesEmulsionParticleFísicaNuclear emulsion010306 general physics01 natural sciencesOmegaParticle Physics - Experiment
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A direct measurement of |Vcs| in hadronic W decays using a charm tag

1999

Abstract The inclusive charm production rate in W decays is measured from a study of the properties of final state particles. The sample of W pairs is selected from 67.7 pb−1 collected by ALEPH in 1996 and 1997 at centre-of-mass energies near 172 and 183 GeV in the channels W+W−→4q and W + W − →lνq q . The branching fraction of hadronic W decays to a final state containing a c quark, RWc= Γ(W→cX)/Γ(W→hadrons), is measured to be 0.51±0.05stat±0.03syst. This allows a direct determination of the CKM matrix element |Vcs|=1.00±0.11stat±0.07syst.

Nuclear physicsPhysicsNuclear and High Energy PhysicsAlephParticle physicsBranching fractionCabibbo–Kobayashi–Maskawa matrixElectron–positron annihilationHadronCharm (quantum number)Particle Physics - ExperimentProduction rateCharm quark
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Isosinglet-neutral heavy-lepton production in Z-decays and neutrino mass

1990

Abstract The possible existence of NHLs is often related to neutrino mass. As a result their production cross section may be correspondingly constrained by observational limits on neutrino masses. We analyze the discovery potential of isosinglet NHLs within various models taking also into account cosmological limits on relic neutrino abundances.

Nuclear physicsPhysicsNuclear and High Energy PhysicsCross section (physics)Particle physicsHigh Energy Physics::PhenomenologyMeasurements of neutrino speedHigh Energy Physics::ExperimentSolar neutrino problemNeutrinoNeutrino oscillationLeptonNuclear Physics B
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Final report on the CERN muon storage ring including the anomalous magnetic moment and the electric dipole moment of the muon, and a direct test of r…

1978

Abstract A comprehensive description of the muon storage ring and its operation is given, and the final results of the experiment are presented and discussed. The anomalous magnetic moments of positive and negative muons are found to be aμ+ = 1165911(11) × 10−9 and aμ− = 1165937(12) × 10−9 giving an average value for muons of aμ = 1165924(8.5) × 10−9. The electric dipole moments were also measured with the results Dμ+= (8.6 ± 4.5) × 10−9e · cm and Dμ− = (0.8 ± 4.3) × 10−19e · cm. Under the assumption of the CPT theorem these yield a weighted average of Dμ = (3.7 ± 3.4) × 10−19e · cm. Finally the time transformation of special relativity is shown to be valid to (0.8 ± 0.7) × 10−3 at γ ≅ 29.3…

Nuclear physicsPhysicsNuclear and High Energy PhysicsDipoleElectric dipole momentParticle physicsMuonMagnetic momentAnomalous magnetic dipole momentCPT symmetryTime dilationParticle Physics - ExperimentStorage ringNuclear Physics B
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The longitudinal muon polarization in KL → μ+μ-

1991

17 páginas, 3 figuras, 1 tabla.-- CERN-TH-6035-91 ; UWTHPH-1991-9.

Nuclear physicsPhysicsNuclear and High Energy PhysicsMuonChiral perturbation theoryAstrophysics::High Energy Astrophysical PhenomenaAnalytical chemistryFísicaPolarization (waves)Particle Physics - Phenomenology
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