Search results for " Simulation"

showing 10 items of 4034 documents

Rates, polarizations, and asymmetries in charmless vector-vector B meson decays

2003

With a sample of approximately 89 million BBbar pairs collected with the BABAR detector, we perform a search for B meson decays into pairs of charmless vector mesons (phi, rho, and K*). We measure the branching fractions, determine the degree of longitudinal polarization, and search for CP violation asymmetries in the processes B->phiK*+, B->phiK*0, B->rho0K*+, and B->rho0rho+. We also set an upper limit on the branching fraction for the decay B->rho0rho0.

Particle physicsMesonBABARElectron–positron annihilationHadronFOS: Physical sciencesGeneral Physics and AstronomyElementary particleResonancePARTICLE PHYSICS; PEP2; BABAR01 natural sciencesNOHigh Energy Physics - ExperimentHigh energy physicHigh Energy Physics - Experiment (hep-ex)Particle decayElectromagnetic calorimeterPolarizationProbability density function0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]PEP2B mesonDecay dynamic010306 general physicsPhysicsCalorimeter010308 nuclear & particles physicsBranching fractionCP-ASYMMETRIES VIOLATION SEARCH B->VVColliding beam acceleratorComputer simulationDecay rateMonte Carlo methodCrystallographyPARTICLE PHYSICSCP violationHigh Energy Physics::ExperimentParticle detectorProton
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Measurements of the branching fractions and bounds on the charge asymmetries of charmless three-body charged B decays.

2003

We present measurements of branching fractions and charge asymmetries for charmless B-meson decays to three-body final states of charged pions and kaons. The analysis uses 81.8 fb^-1 of data collected at the Upsilon(4S) resonance with the BaBar detector at the SLAC PEP-II asymmetric B Factory. We measure the branching fractions B(B+ -> pi+ pi- pi+) = (10.9 +/- 3.3 +/- 1.6) x 10^-6, B(B+ -> K+ pi- pi+) = (59.1 +/- 3.8 +/- 3.2) x 10^-6, and B(B+ -> K+ K- K+) = (29.6 +/- 2.1 +/- 1.6) x 10^-6, and provide 90% C.L. upper limits for other decays. We observe no charge asymmetries for these modes.

Particle physicsMesonBABARHadronCharged particleGeneral Physics and AstronomyFOS: Physical sciencesElementary particlePARTICLE PHYSICS; PEP2; BABAR01 natural sciencesHigh Energy Physics - ExperimentNuclear physicsParticle decayHigh Energy Physics - Experiment (hep-ex)PionSEARCH0103 physical sciencesPEP2[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]B meson010306 general physicsProbabilityPhysics010308 nuclear & particles physicsBranching fractionCerenkov counterComputer simulationB-factoryMonte Carlo methodParticle beamNuclear physicPARTICLE PHYSICSBranching fractionStorage ringParticle beam trackingPhysical review letters
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Measurement of the ZZ cross-section in e(+)e(-) interactions at 183-189 GeV

2001

Measurements of on-shell ZZ production are described, using data collected by DELPHI in 1997 and 1998, at centre-of-mass energies sqrt(s) = 182.6 GeV and 188.6 GeV respectively. Results obtained in each of the final states q qbar q qbar, mu+mu- q qbar, e+e- q qbar, nu nubar q qbar, l+l-l+l-, and nu nubar l+l- are presented. The measured cross-sections for on-shell ZZ production via the tree-level doubly-resonant graphs (NC02) are: sigma_{NC02}(182.6 GeV) = 0.38 +- 0.18 (stat) +- 0.04 (syst) pb, sigma_{NC02}(188.6 GeV) = 0.60 +- 0.13 (stat) +- 0.07 (syst) pb. They are consistent with the Standard Model expectations of 0.25 pb and 0.65 pb at each energy.

Particle physicsNuclear and High Energy PhysicsCOLLISIONSLOWEST ORDER CALCULATIONSPAIR PRODUCTIONENERGIESMONTE-CARLO SIMULATIONFOS: Physical sciences2-PHOTON PROCESSES01 natural sciencesPartícules (Física nuclear)Standard ModelHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)LEP2SEARCH0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]PROGRAM010306 general physicsQCDELPHIPhysics010308 nuclear & particles physicsPhysicsSigmaMONTE-CARLO SIMULATION; LOWEST ORDER CALCULATIONS; PAIR PRODUCTION; 2-PHOTON PROCESSES; ROOT-S=183 GEV; COLLISIONS; PROGRAM; LEP2; ENERGIES; SEARCHLARGE ELECTRON POSITRON COLLIDERPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSFísica nuclearParticle Physics - ExperimentROOT-S=183 GEV
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Measurements of the tau polarisation in Z0 decays

1995

A sample of Z0→τ+τ- events observed in the DELPHI detector at LEP in 1991 and 1992 is analysed to measure the τ polarisation in the exclusive decay channels {Mathematical expression}, {Mathematical expression}, πν, ρν and a1ν. The τ polarisation is also measured with an inclusive hadronic analysis which benefits from a higher efficiency and a better systematic precision than the use of the exclusive decay modes. The results have been combined with those published on the 1990 data. A measurement of the τ polarisation as a function of production angle yields the values for the mean τ polarisation 〈P〉τ=-0.148±0.022 and for the Z0 polarisation PZ=-0.136±0.027. These results are used to determin…

Particle physicsPOLARIZATIONPhysics and Astronomy (miscellaneous)LUND MONTE-CARLOElectron–positron annihilationHadronLEP-SLC ENERGIESElectron01 natural sciencesPartícules (Física nuclear)JET FRAGMENTATIONPARAMETERSNuclear physicsPHYSICSBHABHA SCATTERINGZ-RESONANCE0103 physical sciencesradiative correction[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]RADIATIVE-CORRECTIONS010306 general physicsEngineering (miscellaneous)Detectors de radiacióBhabha scatteringDELPHIPhysics010308 nuclear & particles physicsDetectortau polarizationPolarization (waves)LARGE ELECTRON POSITRON COLLIDERUniversality (dynamical systems)Z resonanceLUND MONTE-CARLO; LEP-SLC ENERGIES; RADIATIVE-CORRECTIONS; BHABHA SCATTERING; JET FRAGMENTATION; Z-RESONANCE; POLARIZATION; PHYSICS; SIMULATION; PARAMETERSSIMULATIONPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIPARTICLE PHYSICSHigh Energy Physics::ExperimentDELPHI; tau polarization; radiative correction; Z resonanceParticle Physics - ExperimentLepton
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A measurement of the photon structure function F-2(gamma) at an average Q(2) of 12 GeV2/c(4)

1995

The hadronic photon structure function F_{2}^{gamma} has been measured in the Q^{2} range from 4 to 30~GeV^2/c^{4} and down to x values of order 0.001, using data taken with the DELPHI detector at LEP between 1991 and 1993. A comparison is made with several F_{2}^{gamma} parameterizations with special emphasis on their low x behaviour. A result on the Q^{2} evolution of F_{2}^{gamma} is presented.

Particle physicsPhotonPhysics and Astronomy (miscellaneous)LEP; DELPHI; hadronic photon structureHadronMONTE-CARLO SIMULATIONStructure (category theory)01 natural sciencesC-4Partícules (Física nuclear)JET FRAGMENTATIONlaw.inventionQ2Nuclear physicsMONTE-CARLO SIMULATION; STRUCTURE-FUNCTION F2; JET FRAGMENTATION; E+E-PHYSICS; QCD; Q2; SCATTERING; ORDERlaw0103 physical sciencesRange (statistics)SCATTERINGhadronic photon structure010306 general physicsDELPHIQuantum chromodynamicsPhysicsE+E-PHYSICS010308 nuclear & particles physicsScatteringEmphasis (telecommunications)DetectorOrder (ring theory)ORDERLEPQCDLARGE ELECTRON POSITRON COLLIDERPhoton structure functionPARTICLE PHYSICS; LARGE ELECTRON POSITRON COLLIDER; DELPHIMass spectrumPARTICLE PHYSICSFísica nuclearSTRUCTURE-FUNCTION F2
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LeptonInjector and LeptonWeighter: A neutrino event generator and weighter for neutrino observatories

2021

We present a high-energy neutrino event generator, called LeptonInjector, alongside an event weighter, called LeptonWeighter. Both are designed for large-volume Cherenkov neutrino telescopes such as IceCube. The neutrino event generator allows for quick and flexible simulation of neutrino events within and around the detector volume, and implements the leading Standard Model neutrino interaction processes relevant for neutrino observatories: neutrino-nucleon deep-inelastic scattering and neutrino-electron annihilation. In this paper, we discuss the event generation algorithm, the weighting algorithm, and the main functions of the publicly available code, with examples.

Particle physicsPhysics::Instrumentation and DetectorsComputer scienceAstrophysics::High Energy Astrophysical PhenomenaFOS: Physical sciencesGeneral Physics and AstronomyCHERENKOV LIGHT YIELDWeighting01 natural sciencesHigh Energy Physics - Experiment010305 fluids & plasmasStandard ModelHigh Energy Physics - Experiment (hep-ex)Neutrino interactionHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciences010306 general physicsCherenkov radiationEvent generatorEvent generator; Neutrino generator; Neutrino interaction; Neutrino simulation; WeightingGenerator (computer programming)hep-exEvent (computing)ICEHigh Energy Physics::PhenomenologyDetectorhep-phComputational Physics (physics.comp-ph)Quantitative Biology::GenomicsHigh Energy Physics - Phenomenologyphysics.comp-phHardware and ArchitectureHigh Energy Physics::ExperimentNeutrino simulationNeutrino generatorEvent generatorNeutrinoPhysics - Computational PhysicsLeptonComputer Physics Communications
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Desipramine induces disorder in cholesterol-rich membranes:implications for viral trafficking

2009

In this study, the effect of desipramine (DMI) on phospholipid bilayers and parvoviral entry was elucidated. In atomistic molecular dynamics simulations, DMI was found to introduce disorder in cholesterol-rich phospholipid bilayers. This was manifested by a decrease in the deuterium order parameter S(CD) as well as an increase in the membrane area. Disordering of the membrane suggested DMI to destabilize cholesterol-rich membrane domains (rafts) in cellular conditions. To relate the raft disrupting ability of DMI with novel biological relevance, we studied the intracellular effect of DMI using canine parvovirus (CPV), a virus known to interact with endosomal membranes and sphingomyelin, as …

Parvovirus CanineEndosomeBiophysicsPhospholipidBiologyAntidepressive Agents Tricyclicchemistry.chemical_compoundDogsStructural BiologyDesipraminemedicineAnimalsComputer SimulationMolecular BiologyCells CulturedMolecular StructureVesicleCell MembraneDesipramineCell BiologyRaftDisease Models AnimalMembraneCholesterolchemistryBiochemistryBiophysicslipids (amino acids peptides and proteins)Sphingomyelinhuman activitiesIntracellularmedicine.drug
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Estimation of Passenger Car Equivalents for single-lane roundabouts using a microsimulation-based procedure

2017

Calibration of microscopic traffic simulation models for single-lane roundabouts.Use of a meta-analytical estimation of critical and follow up headways.Use of a genetic algorithm-based procedure.Calculation of passenger car equivalents for single-lane roundabouts. Passenger car equivalents for heavy vehicles are required to carry out capacity calculations and perform operational analysis of any road entity (roadway segments or intersections). At single-lane roundabouts, the constraints to the vehicular trajectories imposed by the curvilinear geometric design and the driver's gap acceptance behaviour are expected to produce an impact of the heavy vehicles on the quality of traffic flow diffe…

Passenger car equivalent050210 logistics & transportationComputer science05 social sciencesGeneral EngineeringMicrosimulationTraffic simulation02 engineering and technologyTraffic flowAimsunAutomotive engineeringComputer Science ApplicationsGenetic algorithmSettore ING-INF/04 - AutomaticaArtificial IntelligenceCalibration0502 economics and businessPath (graph theory)Roundabout0202 electrical engineering electronic engineering information engineeringSettore ICAR/04 - Strade Ferrovie Ed AeroportiSingle-lane roundabout020201 artificial intelligence & image processingPassenger car equivalentMicroscopic traffic simulation modelExpert Systems with Applications
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Modelling the spatial and temporal constrains of the GABAergic influence on neuronal excitability

2021

GABA (γ-amino butyric acid) is an inhibitory neurotransmitter in the adult brain that can mediate depolarizing responses during development or after neuropathological insults. Under which conditions GABAergic membrane depolarizations are sufficient to impose excitatory effects is hard to predict, as shunting inhibition and GABAergic effects on spatiotemporal filtering of excitatory inputs must be considered. To evaluate at which reversal potential a net excitatory effect was imposed by GABA (EGABAThr), we performed a detailed in-silico study using simple neuronal topologies and distinct spatiotemporal relations between GABAergic and glutamatergic inputs. These simulations revealed for GABAe…

Patch-Clamp TechniquesAction potentialPhysiologyAction PotentialsSynaptic TransmissionNervous SystemBiochemistryMiceNerve FibersAnimal CellsMedicine and Health SciencesGABAergic NeuronsBiology (General)gamma-Aminobutyric AcidNeuronsMembrane potentialEcologyChemistryPyramidal CellsDepolarizationNeurochemistryNeurotransmittersCA3 Region HippocampalElectrophysiologyReceptors GlutamateComputational Theory and MathematicsModeling and SimulationExcitatory postsynaptic potentialGABAergicAnatomyCellular TypesShunting inhibitionResearch Articlemedicine.drugQH301-705.5Models NeurologicalNeurophysiologyAMPA receptorMembrane Potentialgamma-Aminobutyric acidCellular and Molecular NeuroscienceGlutamatergicSpatio-Temporal AnalysisGeneticsmedicineAnimalsComputer SimulationReceptors AMPAReversal potentialMolecular BiologyEcology Evolution Behavior and SystematicsComputational BiologyBiology and Life SciencesNeural InhibitionDendritesCell BiologyNeuronal DendritesAxonsMice Inbred C57BLAnimals Newbornnervous systemCellular NeuroscienceSynapsesDepolarizationNeuroscienceNeurosciencePLOS Computational Biology
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Transportation-cost inequality on path spaces with uniform distance

2008

Abstract Let M be a complete Riemannian manifold and μ the distribution of the diffusion process generated by 1 2 ( Δ + Z ) where Z is a C 1 -vector field. When Ric − ∇ Z is bounded below and Z has, for instance, linear growth, the transportation-cost inequality with respect to the uniform distance is established for μ on the path space over M . A simple example is given to show the optimality of the condition.

Path (topology)Statistics and ProbabilityTransportation-cost inequalityPath spaceApplied MathematicsMathematical analysisRiemannian manifoldManifoldUniform distanceQuasi-invariant flowDistribution functionModeling and SimulationBounded functionModelling and SimulationVector fieldMathematics::Differential GeometryInvariant (mathematics)Damped gradientDistribution (differential geometry)MathematicsStochastic Processes and their Applications
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