Search results for "Mixing"

showing 10 items of 795 documents

Long-term simulations of extragalactic jets: cavities and feedback

2010

AbstractWe present long-term numerical simulations of powerful extragalactic relativistic jets in two dimensions. The jets are injected in a realistic atmosphere with powers 1044, 1045 and 1046 erg/s, during tens of Myrs. After this time, the jet injection is switched off. We follow the evolution of the jets and associated shocks from 1 kpc to hundreds of kiloparsecs during more than 100 Myrs. The 1045 erg/s jet was simulated with leptonic and baryonic composition. Our results show that, for powerful jets, the main heating mechanisms are the driving shock-wave and mixing. We discuss the implications that these results have in the frame of cooling flows in clusters.

PhysicsJet (fluid)Astrophysics::High Energy Astrophysical PhenomenaAstronomyAstronomy and AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsTerm (time)AtmosphereBaryonAstrophysical jetSpace and Planetary ScienceJet injectionAstrophysics::Galaxy AstrophysicsMixing (physics)Proceedings of the International Astronomical Union
researchProduct

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
researchProduct

Counter-propagating difference-frequency generation in diamond with terahertz fields

2013

The nonlinear interaction of terahertz (THz) pulses with optical fields in Kerr, gaseous media is a key ingredient for broadband THz detection schemes [1]. Terahertz field-induced second harmonic generation in solid-state media has also been considered for THz detection and as a tool e.g. for liquid dynamics investigations [2,3], while four-wave mixing has been addressed as a possible mechanism for THz generation [4,5]. © 2013 IEEE.

PhysicsKerr effectSum-frequency generationTerahertz radiationbusiness.industryNonlinear opticPhysics::OpticsDiamondSecond-harmonic generationengineering.materialSettore ING-INF/01 - ElettronicaTerahertz spectroscopy and technologyFour-wave mixingOpticsCross-polarized wave generationQuantum electronicsengineeringOptoelectronicsbusiness
researchProduct

Configurational entropy of microemulsions : The fundamental length scale

1993

Phenomenological models have been quite successful in characterizing both the various complex phases and the corresponding phase diagrams of microemulsions. In some approaches, e.g., the random mixing model (RMM), the lattice parameter is of the order of the dimension of an oil or water domain and has been used as a length scale for computing a configurational entropy, the so‐called entropy of mixing, of the microemulsion. In the central and material section of this paper (Sec. III), we show that the fundamental length scale for the calculation of the entropy of mixing is of the order of the cube root of the volume per molecule—orders of magnitude smaller than the dimension of such a domain…

PhysicsLength scalePhase StudiesEntropyConfiguration entropyGeneral Physics and AstronomyThermodynamicsEntropy of mixingMicroemulsions ; Entropy ; Phase Diagrams ; Lattice Parameters ; Dispersions ; Phase StudiesUNESCO::FÍSICA::Química físicaPhase spacePhenomenological modelMicroemulsionsLattice ParametersStatistical physicsConfiguration spacePhase DiagramsPhysical and Theoretical ChemistryEntropy (energy dispersal)Dispersions:FÍSICA::Química física [UNESCO]Cube root
researchProduct

Two frequency oscillation of a photorefractive oscillator as a perturbation of the mirrorless oscillation

2010

We consider the properties of the non-degenerate two frequency regime of oscillation of the semi-linear photorefractive oscillator and analyze its relation with the mirrorless oscillation. We consider the oscillator with or without a frequency shifted feedback by a vibrating mirror. This study shows that these two apparently different phenomena are closely related. We conclude from the obtained results that the two frequency oscillation can be considered as a perturbation of the mirrorless oscillation.

PhysicsLight intensityFour-wave mixingOscillationQuantum mechanicsPerturbation (astronomy)Light beamStatistical and Nonlinear PhysicsPhotorefractive effectPhase conjugationAtomic and Molecular Physics and OpticsPockels effectJournal of the Optical Society of America B
researchProduct

Electromagnetic Multipole Moments and Transitions

2007

In the preceding chapter we constructed and discussed the simplest possible nuclear wave functions. This construction was done at the mean-field level. No account was taken of configuration mixing caused by the nuclear residual interaction. These simple wave functions produce degeneracies in energy spectra. This is contrary to experimental data, so improved wave functions are called for.

PhysicsMagnetic momentSimple (abstract algebra)Quantum electrodynamicsMultipole expansionResidualWave functionEnergy (signal processing)Mixing (physics)Spectral line
researchProduct

Limits onD0−D¯0Mixing andCPViolation from the Ratio of Lifetimes for Decay toK−π+,K−K+, andπ−π+

2003

We present a measurement of D0-macro D0 mixing parameters using the ratios of lifetimes extracted from samples of D0 mesons decaying to K-pi(+), K-K+, and pi(-)pi(+). Using 91 fb(-1) of data collected by the BABAR detector at the PEP-II asymmetric-energy B Factory, we obtain a value Y=[0.8+/-0.4(stat.)(+0.5)(-0.4)(syst.)]%, which, in the limit of CP conservation, corresponds to the mixing parameter y=Delta Gamma/2 Gamma. Using the difference in lifetimes of D0 and macro D0 mesons, we obtain the CP-violation parameter Delta Y=[-0.8+/-0.6(stat.)+/-0.2(syst.)]%.

PhysicsMeson010308 nuclear & particles physicsElectron–positron annihilationAnalytical chemistryGeneral Physics and AstronomyValue (computer science)01 natural sciencesB-factoryNuclear physicsParticle decay0103 physical sciencesPiCP violationHigh Energy Physics::Experiment010306 general physicsMixing (physics)Physical Review Letters
researchProduct

Do organics contribute to small particle formation in the Amazonian upper troposphere?

2008

3-D cloud-resolving model simulations including explicit aerosol physics and chemistry are compared with observations of upper tropospheric (12 km) aerosol size distributions over the Amazon Basin. ...

PhysicsMeteorologyAmazonianAtmospheric sciencesAerosolTroposphereBoundary layerGeophysicsParticle-size distributionMixing ratioGeneral Earth and Planetary SciencesSmall particlesPhysics::Atmospheric and Oceanic PhysicsAmazon basinGeophysical Research Letters
researchProduct

Strong four-photon conversion regime of cross-phase-modulation-induced modulational instability

2000

We investigate theoretically and experimentally the strong conversion regime of parametric four-photon amplification or induced modulational instability in the normal dispersion regime of propagation in a highly birefringent fiber. Such optical mixing is observed by injecting a tunable linearly polarized (along the fast axis) anti-Stokes signal wave copropagating with a pump equisplitted between the fiber axes (i.e., linearly polarized at 45\ifmmode^\circ\else\textdegree\fi{}) which entail that the two pump modes experience cross-phase modulation. In agreement with a four-wave model developed to study the depleted regime of the mixing process, we observe that the strongest conversion occurs…

PhysicsModulational instabilityWave propagationLinear polarizationModulationCross-phase modulationQuantum mechanicsDispersion (optics)Physics::OpticsAtomic physicsBeam (structure)Mixing (physics)Physical Review E
researchProduct

Propagation, Stability and Interactions of Novel Three-Wave Parametric Solitons

2006

International audience; We found a new class of analytic soliton solutions that describe the parametric wave mixing of optical pulses in quadratic nonlinear crystals. We analyze the stability properties, interactions and collisions of these solitons.

PhysicsMultidisciplinarySilicon photonicsPartial differential equationMaterials ScienceOptics02 engineering and technology01 natural sciencesOptical parametric amplifierDissipative solitonEngineeringNonlinear Sciences::Exactly Solvable and Integrable Systems020210 optoelectronics & photonicsClassical mechanicsQuantum mechanics0103 physical sciences0202 electrical engineering electronic engineering information engineeringElectrical & ElectronicPeregrine solitonSoliton010306 general physicsNonlinear Sciences::Pattern Formation and SolitonsMixing (physics)Parametric statistics2006 IEEE LEOS Annual Meeting Conference Proceedings
researchProduct