Search results for "scattering [electron hadron]"

showing 10 items of 654 documents

Comparison of theory and experiment

1991

In this section we are finally going to confront experimental data on total cross section, angular distributions and polarization observables with theoretical results in order to establish the present status of our knowledge of this important process. We hope this will enable us to set directions and guidelines for future experimental and theoretical studies, which kind of experiments are needed and what accuracy should be aimed for, where theoretical studies should be extended, on what they should focus and whether some basic assumptions need to be modified. For the comparison we shall use mostly the data of experiments selected in sections 6.3 and 6.4, the relative quantities and the best…

Set (abstract data type)Scattering cross-sectionCross section (physics)Computer scienceSection (archaeology)Process (engineering)Polarization observablesCalculusExperimental dataFocus (optics)
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Rateless Codes Performance Analysis in Correlated Channel Model for GEO Free Space Optics Downlinks

2012

Settore ING-INF/03 - TelecomunicazioniFree Space Optics (FSO) technologies for satellite communications offer several advantages: wide bandwidth high rate capability immunity to electromagnetic interference and small equipment size. Thus they are suitable for inter-satellite links deep space communications and also for high data rate ground-to-satellite/satellite-to-ground communications. Nevertheless FSO links suffer impairments that cause power signal degradation at the receiver. Scattering and absorption cause power signal attenuations predictable by suitable deterministic models. Optical turbulence causes random irradiance fluctuations which can generate signal fading events and can thereby only be predicted by statistical models. Attenuation and fading events can corrupt FSO links and so it would be recommended to add mitigation error codes on the communication link. FSO channel can be described as an erasure channel: fading events can cause erasure errors. We have identified in rateless codes (RCs) a suitable solution to be employed in FSO links. RCs do not need feedback and they add a redundant coding on the source data that allows the receiver to recover the whole payload despite erasure errors. We implemented two different of rateless codes: Luby Transform (LT) and Raptor. We analyzed their performances on a simulated turbulent GEO FSO downlink (1 Gbps - OOK modulation) at a 106 μm wavelength and for different values of zenith angles. Assuming a plane-wave propagation and employing Hufnagel-Valley we modeled the downlink using: 1) a temporal correlated channel model based on Gamma-Gamma probability distribution and 2) an irradiance covariance function that we converted on a time function using Taylor frozen eddies hypothesis. Our new channel model is able to simulate irradiance fluctuations at different turbulence conditions as it will be shown in the full paper. We will also report performance results of LT and Raptor codes at overhead range varying between 0 and 50% and for different values of source packets.Settore ING-INF/01 - Elettronica
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Broadband photocurrent enhancement in a-Si:H solar cells with plasmonic back reflectors

2014

The authors acknowledge Francesco Ruffino for the AFM measurements. This work was funded by the EU FP7 Marie Curie Action FP7-PEOPLE-2010-ITN through the PROPHET project (Grant No. 264687), the bilateral CNR/AVCR project "Photoresponse of nanostructures for advanced photovoltaic applications", the MIUR project Energetic (Grant no. PON02_00355_3391233) and by the Portuguese Science Foundation (FCT-MEC) through the Strategic Project PEst-C/CTM/LA0025/2013-14 and the research project PTDC/CTM-ENE/2514/2012. Plasmonic light trapping in thin film silicon solar cells is a promising route to achieve high efficiency with reduced volumes of semiconductor material. In this paper, we study the enhance…

SiliconMaterials scienceConformal growthSiliconchemistry.chemical_elementPlasmon02 engineering and technologyFILMS01 natural sciences7. Clean energySilver A-Si:H solar cellSettore ING-INF/01 - ElettronicaLight scatteringOptics0103 physical sciencesPhotocurrentFabrication parameterPlasmonic solar cellThin filmSILICONPhotocurrent enhancementPlasmon010302 applied physicsPhotocurrentbusiness.industryLight scattering021001 nanoscience & nanotechnologySolar energyScattering effectAtomic and Molecular Physics and OpticschemistryDiffuse reflectionOptoelectronicsDiffuse reflectionThin-film silicon solar cells Silicon solar cells0210 nano-technologybusinessSilver nanoparticle (NPs)Optics Express
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Impact of dust and smoke mixing on column-integrated aerosol properties from observations during a severe wildfire episode over Valencia (Spain)

2017

The most destructive wildfire experienced in Spain since 2004 occurred close to Valencia in summer 2012. A total of 48.500ha were affected by two wildfires, which were mostly active during 29-30 June. The fresh smoke plume was detected at the Burjassot measurement station simultaneously to a severe dust episode. We propose an empirical method to evaluate the dust and smoke mixing and its impact on the microphysical and optical properties. For this, we combine direct-sun measurements with a Cimel CE-318 sun-photometer with an inversion methodology, and the Mie theory to derive the column-integrated size distribution, single scattering albedo (SSA) and asymmetry parameter (g). The mixing of d…

SmokeEnvironmental Engineering010504 meteorology & atmospheric sciencesSingle-scattering albedoMie scatteringMixing (process engineering)010501 environmental sciencesAlbedoMineral dustAtmospheric sciencescomplex mixtures01 natural sciencesPollutionAerosolWavelengthEnvironmental ChemistryEnvironmental scienceWaste Management and Disposal0105 earth and related environmental sciencesScience of The Total Environment
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Polymer-based materials modified with magnetite nanoparticles for enrichment of phospholipids

2018

[EN] A polymeric material modified with magnetic nanoparticles (MNPs) has been synthesized and evaluated as sorbent both for solid-phase extraction (SPE) and dispersive magnetic solid-phase extraction (MSPE) of phospholipids (PLs) in human milk samples. The synthesized sorbent was characterized by scanning electron microscopy and its iron content was also determined. Several experimental variables that affect the extraction performance (e.g. loading solvent, breakthrough volume and loading capacity) were investigated and a comparison between conventional SPE and MSPE modalities was done. The proposed method was satisfactorily applied to the analysis of PLs in human milk fat extracts in diff…

SorbentScanning electron microscope010402 general chemistry01 natural sciencesAnalytical ChemistryLimit of DetectionQUIMICA ANALITICAHumansSolid phase extractionChromatography-evaporative light scattering detectionMagnetite NanoparticlesChromatography High Pressure LiquidPhospholipidschemistry.chemical_classificationSolid-phase extractionChromatographyHydrophilic interaction liquidMilk HumanHydrophilic interaction chromatography010401 analytical chemistryExtraction (chemistry)Solid Phase ExtractionHuman milkPolymer0104 chemical sciencesSolventchemistryMagnetic nanoparticlesEpoxy CompoundsMethacrylatesMagnetic polymer-based materialHydrophobic and Hydrophilic Interactions
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Experimental results for two-particle break-up

1991

In this section we shall review the present status of experiments on two-body photo-disintegration of deuteron up to and above the Δ region. The results of different experiments will be discussed and a guideline will be given for a selection of the experiments to be used in the comparison of experimental data with theoretical results. Moreover, since a large variety of observables exists, which have been studied experimentally, we shall discuss which kind of measured quantities, having a smaller systematic error, can give more accurate information.

Systematic errorPhysicsScattering cross-sectionBreak-UpSection (archaeology)Experimental dataParticleObservableStatistical physics
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Thermally induced structural modifications and O2 trapping in highly porous silica nanoparticles

2014

Abstract In this work we investigate by Raman spectroscopy the effect of isochronal (2 h) thermal treatments in air in the temperature range 200–1000 °C of amorphous silicon dioxide porous nanoparticles with diameters ranging from 5 up to 15 nm and specific surface 590–690 m2/g. Our results indicate that the amorphous structure changes similarly to other porous systems previously investigated, in fact superficial SiOH groups are removed, Si–O–Si linkages are created and the ring statistic is modified, furthermore these data evidence that the three membered rings do not contribute significantly to the Raman signal detected at about 495 cm−1. In addition, after annealing at 900 and 1000 °C we…

Thin layersMaterials scienceSettore FIS/01 - Fisica SperimentaleAnalytical chemistryNanoparticleAtmospheric temperature rangeCondensed Matter Physicslaw.inventionAmorphous solidNanostructures Amorphous materials Luminescence Raman spectroscopy and scattering Heat treatment Porous silicasymbols.namesakelawsymbolsGeneral Materials ScienceSurface layerElectron paramagnetic resonancePorous mediumRaman spectroscopy
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Search for a heavy top-quark partner in final states with two leptons with the ATLAS detector at the LHC

2012

The results of a search for direct pair production of heavy top-quark partners in 4.7 fb[superscript −1] of integrated luminosity from pp collisions at s√ = 7 TeV collected by the ATLAS detector at the LHC are reported. Heavy top-quark partners decaying into a top quark and a neutral non-interacting particle are searched for in events with two leptons in the final state. No excess above the Standard Model expectation is observed. Limits are placed on the mass of a supersymmetric scalar top and of a spin-1/2 top-quark partner. A spin-1/2 top-quark partner with a mass between 300 GeV and 480 GeV, decaying to a top quark and a neutral non-interacting particle lighter than 100 GeV, is excluded …

Top quark01 natural sciences7. Clean energyHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]Nuclear ExperimentQCPhysicsddc:539Large Hadron ColliderLuminosity (scattering theory)[SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]Settore FIS/01 - Fisica SperimentaleSupersymmetryATLASComputer Science::Computers and Societyhmedicine.anatomical_structurehadron-hadronComputingMethodologies_DOCUMENTANDTEXTPROCESSINGFísica nuclearLHCParticle Physics - ExperimentParticle physicsNuclear and High Energy Physics[PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE]leptonsCiências Naturais::Ciências Físicas:Ciências Físicas [Ciências Naturais]FOS: Physical sciences530Standard ModelNuclear physicsAtlas (anatomy)0103 physical sciencesmedicinePhysics::Atomic and Molecular Clustersddc:530High Energy Physics010306 general physicsCiencias ExactasHadron-Hadron scattering; Nuclear and High Energy PhysicsHadron-Hadron ScatteringScience & TechnologyATLAS detector010308 nuclear & particles physicsscatteringHigh Energy Physics::PhenomenologyFísicaPair productionNonlinear Sciences::Exactly Solvable and Integrable SystemsHADRON-HADRON COLLISIONSExperimental High Energy PhysicsHigh Energy Physics::ExperimentsupersymmetryLeptonhadron-hadron; hadron-hadron scattering; scattering
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Measurement of thett¯production cross section inpp¯collisions ats=1.96  TeVusing soft electronb-tagging

2010

The authors present a measurement of the t{bar t} production cross section using events with one charged lepton and jets from p{bar p} collisions at a center-of-mass energy of 1.96 TeV. A b-tagging algorithm based on the probability of displaced tracks coming from the event interaction vertex is applied to identify b quarks from top decay. Using 318 pb{sup -1} of data collected with the CDF II detector, they measure the t{bar t} production cross section in events with at least one restrictive (tight) b-tagged jet and obtain 8.9{sub -1.0}{sup +1.0}(stat.){sub -1.0}{sup +1.1}(syst.) pb. The cross section value assumes a top quark mass of m{sub t} is presented in the paper. This result is cons…

Top quarkCollider physicsHadronTevatronGeneral Physics and AstronomyElementary particleKinematicsElectronJet (particle physics)01 natural sciences7. Clean energyParticle identificationlaw.inventionlawInvariant massFermilabNuclear ExperimentQuantum chromodynamicsPhysicsLarge Hadron ColliderLuminosity (scattering theory)Supersymmetryb-taggingHadronizationTransverse planeProduction (computer science)Collider Detector at FermilabQuarkSemileptonic decayNuclear and High Energy PhysicsParticle physicsBar (music)Astrophysics::High Energy Astrophysical PhenomenaBottom quarkMeasure (mathematics)Standard ModelNuclear physicsCross section (physics)Particle decay0103 physical sciencesCollider010306 general physicsCompact Muon SolenoidMuonBranching fraction010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyMultiplicity (mathematics)FermionVertex (geometry)Pair productionHigh Energy Physics::ExperimentEnergy (signal processing)Bar (unit)LeptonPhysical Review D
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Cross-section-constrained top-quark mass measurement from dilepton events at the tevatron

2008

We report the first top quark mass measurement that uses a cross section constraint to improve the mass determination. This measurement is made with a dilepton $t\bar{t}$ event sample collected with the CDF II detector. From a data sample corresponding to an integrated luminosity of 1.2 fb$^{-1}$, we measure a top quark mass of $\rm{170.7^{+4.2}_{-3.9}(stat)\pm2.6(syst)}$ $\rm{\pm2.4(theory) GeV/{\it{c}}^{2}}$. The measurement without the cross section constraint results in a top quark mass of $\rm{169.7^{+5.2}_{-4.9}(stat)\pm3.1(syst) GeV/{\it{c}}^{2}}$.

Top quarkParticle physicsPhysics MultidisciplinaryTevatronFOS: Physical sciencesGeneral Physics and Astronomyddc:500.2Molecular dynamics01 natural sciencesHigh Energy Physics - Experimentlaw.inventionNuclear physicsHigh Energy Physics - Experiment (hep-ex)Colliding beam acceleratorslaw0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]FermilabHigh energy physicsNuclear Experiment010306 general physicsColliderConstraint theoryAstrophysics::Galaxy AstrophysicsPhysicsLuminosity (scattering theory)010308 nuclear & particles physicsPhysicsHigh Energy Physics::PhenomenologyDetector14.65.Ha 13.85.Ni 13.85.Qk 12.15.FfIntegrated controlConstraint (information theory)Collider DetectorFermi levelCross-section constraintsHigh Energy Physics::ExperimentEvent (particle physics)Top-quark mass measurement
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