Search results for "Interactions"

showing 10 items of 1963 documents

Solutions via double wave ansatz to the 1-D non-homogeneous gas-dynamics equations

2020

Abstract In this paper classes of double wave solutions of the 1D Euler system describing a ideal fluid in the non-homogeneous case have been determined. In order that the analytical procedure under interest to hold, suitable model laws for the source term involved in the governing model were characterized. Finally such a class of exact double wave solutions has been used for solving some problems of interest in nonlinear wave propagation.

PhysicsApplied MathematicsMechanical EngineeringMathematical analysisPerfect fluid02 engineering and technologyGas dynamicsDouble wave solutionsNonlinear wave interactionsEuler system021001 nanoscience & nanotechnologyRiemann problemDouble wave solutions; Hyperbolic systems; Nonlinear wave interactions; Riemann problemTerm (time)Nonlinear wave propagationHyperbolic systems020303 mechanical engineering & transports0203 mechanical engineeringMechanics of MaterialsNon homogeneousOrder (group theory)0210 nano-technologySettore MAT/07 - Fisica MatematicaAnsatz
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The Zoo of emission lines in the spectrum of Cir X-1 observed by XMM-Newton

2007

We present the preliminary analysis of a 10 ks XMM-Newton EPIC/pn observation of Cir X-1 immediately after the zero phase. The continuum emission is modeled using a blackbody component partially absorbed by neutral matter probably located around the binary system. We detect a forest of emission lines associated to highly ionized ions.

PhysicsAstrophysics::High Energy Astrophysical PhenomenaAstronomyAtomic and molecular dataAstrophysicsAtomic processes and interactionSpectraEPICPolarization (waves)Spectral parametersPhotoionization of atoms and ionPreliminary analysisIonIonizationBlack-body radiationEmission spectrumBinary systemAtomic and molecular data; Atomic processes and interactions; Photoionization of atoms and ions; Spectra; Spectral parameters
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Size-consistent self-consistent configuration interaction from a complete active space : Excited states

1998

The self-consistent size consistent on a complete active space singly and doubly configuration interaction (SC)2CAS-SDCI method is applied to excited states. The (SC)2 correction is performed on a closed shell state, and the excited states are obtained by diagonalization of the dressed matrix. A theoretical justification of the transferability of the improvement concerning the dressing state to all roots of the matrix is presented. The method is tested by three tests on the spectrum of small molecules. sanchezm@uv.es ; nebot@uv.es

PhysicsConfiguration interactionsSpectrum (functional analysis)Excited statesGeneral Physics and AstronomyMultireference configuration interactionState (functional analysis)Configuration interactionExcited states ; Configuration interactionsUNESCO::FÍSICA::Química físicaMatrix (mathematics)Excited stateComplete active spacePhysical and Theoretical ChemistryAtomic physics:FÍSICA::Química física [UNESCO]Open shell
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Noise effects in two different biological systems

2009

We investigate the role of the colored noise in two biological systems: (i) adults of Nezara viridula (L.) (Heteroptera: Pentatomidae), and (ii) polymer translocation. In the first system we analyze, by directionality tests, the response of N. viridula individuals to subthreshold signals plus noise in their mating behaviour. The percentage of insects that react to the subthreshold signal shows a nonmonotonic behaviour, characterized by the presence of a maximum, as a function of the noise intensity. This is the signature of the non-dynamical stochastic resonance phenomenon. By using a “soft” threshold model we find that the maximum of the input-output cross correlation occurs in the same ra…

PhysicsFluctuation phenomena random processes noise and Brownian motionQuantitative Biology::BiomoleculesCondensed matter physicsBistabilityStochastic resonanceStochastic processMolecular dynamics Brownian dynamicThermal fluctuationsMolecular interactionWhite noiseNoise in biological systemCondensed Matter PhysicsMolecular physicsSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Electronic Optical and Magnetic MaterialsColors of noiseBrownian dynamicsPolymermembrane-protein interactionsNoise (radio)Biophysical mechanisms of interaction
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ICHEP 2014 Summary: Theory Status after the First LHC Run

2016

A brief overview of the main highlights discussed at ICHEP 2014 is presented. The experimental data confirm that the scalar boson discovered at the LHC couples to other particles as predicted in the Standard Model. This constitutes a great success of the present theoretical paradigm, which has been confirmed as the correct description at the electroweak scale. At the same time, the negative searches for signals of new phenomena tightly constrain many new-physics scenarios, challenging previous theoretical wisdom and opening new perspectives in fundamental physics. Fresh ideas are needed to face the many pending questions unanswered within the Standard Model framework.

PhysicsHigh Energy Physics - TheoryNuclear and High Energy PhysicsParticle physicsLarge Hadron ColliderStandard Model and Beyond010308 nuclear & particles physicsPhysics beyond the Standard ModelElectroweak interactionFOS: Physical sciencesScalar boson01 natural sciencesStandard ModelHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics - Theory (hep-th)0103 physical sciencesFundamental physicsElectroweak and Strong InteractionsHigh Energy PhysicsElectroweak scale010306 general physics
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Observation of collapse arrest in pure kerr media sustained by a parametric interaction

2013

We demonstrate a parametric interaction based on four wave mixing that can arrest the collapse and stabilize solitary propagation in a pure Kerr material by controlling the wavelength of the interacting beams.

PhysicsKerr effectCollapse (topology)Physics::OpticsCollapse arrestSettore ING-INF/01 - ElettronicaSolitary propagationWavelengthFour-wave mixingKerr mediaParametric interactionsQuantum electrodynamicsQuantum mechanicsKerr materialsLight beamNonlinear OpticsPhase velocityRefractive indexNonlinear Sciences::Pattern Formation and SolitonsParametric statistics
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Translationally invariant coupled cluster method in coordinate space for nuclei

2002

We study a formulation of the translationally invariant coupled cluster method in coordinate space for finite nuclei. The new formulation remedies convergence problems that plagued previous calculations in configuration space. The method is applied to light nuclei using semi-realistic central interactions.

PhysicsLight nucleusNuclear and High Energy Physics/dk/atira/pure/subjectarea/asjc/3100/3106Nuclear structureInvariant (physics)Physics and Astronomy(all)Coupled clusterClassical mechanics/dk/atira/pure/subjectarea/asjc/3100Quantum electrodynamicsNuclear binding energyConfiguration spaceCLOSED-SHELL NUCLEI; MODEL-CALCULATIONS; CBF THEORY; DEPENDENT CORRELATIONS; PAIR CORRELATIONS; FINITE SYSTEMS; GROUND-STATE; JASTROW; O-16; Nuclear binding energy; Nuclear model; Nuclear structure; Nucleon-nucleon potential (formulation of translationally invariant coupled cluster method in coordinate space for closed shell nuclei within 0p-shell with use of semi-realistic central nucleon-nucleon interactions)Coordinate spaceGround state
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Elastic waves propagation in 1D fractional non-local continuum

2008

Aim of this paper is the study of waves propagation in a fractional, non-local 1D elastic continuum. The non-local effects are modeled introducing long-range central body interactions applied to the centroids of the infinitesimal volume elements of the continuum. These non-local interactions are proportional to a proper attenuation function and to the relative displacements between non-adjacent elements. It is shown that, assuming a power-law attenuation function, the governing equation of the elastic waves in the unbounded domain, is ruled by a Marchaud-type fractional differential equation. Wave propagation in bounded domain instead involves only the integral part of the Marchaud fraction…

PhysicsNon-local elasticityContinuum mechanicsWave propagationDifferential equationMathematical analysisCondensed Matter PhysicsFractional calculuDispersion of elastic waves; Lattice models; Long-range interactions; Non-local elasticity; Fractional calculus; Fractional power lawPower lawAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsFractional calculusLattice modelLove waveLong-range interactionIngenieurwissenschaftenDispersion of elastic waveBounded functionddc:620Settore ICAR/08 - Scienza Delle CostruzioniLongitudinal waveFractional power law
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Evidence of the same multiparticle production mechanism in p−p collisions as in e+e− annihilation

1980

The split-field magnet spectrometer at the CERN intersecting storage rings was used to measure, in p-p collisions at square root s=62 GeV, the inclusive momentum distribution of the charged particles produced in the same hemisphere as the leading proton (x>0.4). A new scaling variable was introduced in order to take into account baryon-number conservation effects in p-p interactions. It is shown that distributions in this variable are in good agreement with the momentum distribution of the hadrons produced in e/sup +/e/sup -/ annihilation. The results suggest that the multiparticle production mechanism in p-p collisions is the same as in e/sup +/e/sup -/ provided that the effects of baryon-…

PhysicsNuclear and High Energy PhysicsParticle physicsAnnihilationLarge Hadron ColliderProtonIntersecting Storage RingsElectron–positron annihilationSettore FIS/01 - Fisica SperimentaleHadronproton-proton inclusive interactions Particle Physics ISR CERNCharged particleNuclear physicsMomentumNuclear ExperimentParticle Physics - ExperimentPhysics Letters B
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Cosmological radiation density with non-standard neutrino-electron interactions

2021

Neutrino non-standard interactions (NSI) with electrons are known to alter the picture of neutrino decoupling from the cosmic plasma. NSI modify both flavour oscillations through matter effects, and the annihilation and scattering between neutrinos and electrons and positrons in the thermal plasma. In view of the forthcoming cosmological observations, we perform a precision study of the impact of non-universal and flavour-changing NSI on the effective number of neutrinos, $N_{eff}$. We present the variation of $N_{eff}$ arising from the different NSI parameters and discuss the existing degeneracies among them, from cosmology alone and in relation to the current bounds from terrestrial exper…

PhysicsNuclear and High Energy PhysicsParticle physicsCosmology and Nongalactic Astrophysics (astro-ph.CO)CosmologiaAnnihilationNeutrino interactionsScatteringNeutrino oscillationsPhysicsQC1-999FOS: Physical sciencesFísicaElectronNeutrino decouplingPlasmaCosmologyCosmologyHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Astrophysical plasmaHigh Energy Physics::ExperimentNon-standard neutrino interactionsNeutrinoAstrophysics - Cosmology and Nongalactic Astrophysics
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