Search results for "ORIENTATION"

showing 10 items of 1041 documents

THE ORIENTATION OF GALAXIES IN GALAXY CLUSTERS

2010

We present an analysis of the spatial orientations of galaxies in the 247 optically selected rich Abell clusters, having in the considered area at least 100 members. We investigated the relation between angles giving information about galaxy angular momenta and the number of members in each structure. The position angles of the galaxy major axes, as well as two angles describing the spatial orientation of galaxy plane were tested for isotropy, by applying three different statistical tests. It is found that the values of statistics increase with the amount of galaxies' members, which is equivalent to the existence of the relation between anisotropy and number of galaxies in cluster. The sear…

PhysicsCosmology and Nongalactic Astrophysics (astro-ph.CO)Plane (geometry)IsotropyFOS: Physical sciencesVelocity dispersionAstronomy and AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsGalaxySpace and Planetary ScienceOrientation (geometry)Cluster (physics)AnisotropyGalaxy clusterAstrophysics - Cosmology and Nongalactic AstrophysicsThe Astrophysical Journal
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Chaotization of internal motion of excitons in ultrathin layers by spin–orbit coupling

2018

We show that Rashba spin-orbit coupling (SOC) can generate chaotic behavior of excitons in two-dimensional semiconductor structures. To model this chaos, we study a Kepler system with spin-orbit coupling and numerically obtain a transition to chaos at a sufficiently strong coupling. The chaos emerges since the SOC reduces the number of integrals of motion as compared to the number of degrees of freedom. Dynamically, the dependence of the exciton energy on the spin orientation in the presence of SOC produces an anomalous spin-dependent velocity resulting in chaotic motion. We observe numerically the critical dependence of the dynamics on the initial conditions, where the system can return to…

PhysicsCouplingChaoticDegrees of freedom (physics and chemistry)General Physics and AstronomyEquations of motion02 engineering and technologySpin–orbit interaction021001 nanoscience & nanotechnology01 natural sciencessymbols.namesakeClassical mechanicsKepler problemOrientation (geometry)0103 physical sciencessymbolsPhysical and Theoretical Chemistry010306 general physics0210 nano-technologySpin-½Physical Chemistry Chemical Physics
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Simple Models for Wall Effect in Fiber Suspension Flows

2014

Jeffery's equation describes the dynamics of a non-inertial ellipsoidal particle immersed in a Stokes liquid and is used in various models of fiber suspension flow. However, it is not valid in close neighbourhood of a rigid wall. Geometrically impossible orientation states with the fiber penetrating the wall can result from this model. This paper proposes a modification of Jeffery's equation in close proximity to a wall so that the geometrical constraints are obeyed by the solution. A class of models differing in the distribution between the translational and rotational part of the response to the contact is derived. The model is upscaled to a Fokker–Planck equation. Another microscale mode…

PhysicsDynamics (mechanics)MechanicsCollisionPhysics::Fluid DynamicsDistribution (mathematics)Flow (mathematics)RheologyModeling and SimulationOrientation (geometry)QA1-939rheologyFiberfiber suspensionwall effectMathematicsAnalysisMicroscale chemistryMathematical Modelling and Analysis
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A First Assessment of the Corrections for the Consistency of the IAU2000 and IAU2006 Precession-Nutation Models

2020

The Earth precession-nutation model endorsed by resolutions of each the International Astronomical Union and the International Union of Geodesy and Geophysics is composed of two theories developed independently, namely IAU2006 precession and IAU2000A nutation. The IAU2006 precession was adopted to supersede the precession part of the IAU 2000A precession-nutation model and tried to get the new precession theory dynamically consistent with the IAU2000A nutation. However, full consistency was not reached, and slight adjustments of the IAU2000A nutation amplitudes at the micro arcsecond level were required to ensure consistency. The first set of formulae for these corrections derived by Capita…

PhysicsEarth rotation theoryEarth Orientation ParametersEarth rotation modelsConsistency (statistics)NutationPrecessionMatemática AplicadaEarth orientation parametersGeodesyPrecession-nutation
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ERRATUM: “MOJAVE. X. PARSEC-SCALE JET ORIENTATION VARIATIONS AND SUPERLUMINAL MOTION IN ACTIVE GALACTIC NUCLEI” (2013, AJ, 146, 120)

2016

PhysicsJet (fluid)Superluminal motionActive galactic nucleus010504 meteorology & atmospheric sciencesScale (ratio)AstronomyAstronomy and AstrophysicsAstrophysics01 natural sciencesParsecSpace and Planetary ScienceOrientation (geometry)0103 physical sciences010303 astronomy & astrophysics0105 earth and related environmental sciencesThe Astronomical Journal
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The baryon number two system in the Chiral Soliton Model

2012

We study the interaction between two B = 1 states in a chiral soliton model where baryons are described as non-topological solitons. By using the hedgehog solution for the B = 1 states we construct three possible B = 2 configurations to analyze the role of the relative orientation of the hedgehog quills in the dynamics. The strong dependence of the intersoliton interaction on these relative orientations reveals that studies of dense hadronic matter using this model should take into account their implications.

PhysicsMatterNuclear TheoryHadronNuclear TheoryHigh Energy Physics::PhenomenologyFOS: Physical sciencesAtomic and Molecular Physics and OpticsChiral solitonBaryonOrientation (vector space)Nuclear Theory (nucl-th)Theoretical physicsFísica nuclearBaryon number
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Geometric efficiency for a circular detector and a linear source of arbitrary orientation and position

2010

A new axisymmetric radiation vector potential which is singular along its entire axis of symmetry is derived for a spherically symmetric point radiation source. This potential and a previously given non-singular point source potential are integrated to give radiation vector potentials for a straight linear source of constant strength. Analytical solutions are given for the geometric efficiency G of a line source and a circular disk detector when the line source is parallel to the detector axis. The analytical solution is also given for the case where the line source is parallel to the disk surface, such that the source axis and the detector axis intersect. All other cases are given as simpl…

PhysicsNuclear and High Energy PhysicsClassical mechanicsPlane (geometry)Position (vector)Point sourceOrientation (geometry)Mathematical analysisDetectorRotational symmetryInstrumentationLine sourceVector potentialNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
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Photo-transmutation of leptons

2001

By photo-transmutation of leptons we mean photon-lepton reactions of the following type: $\gamma l_\alpha \longrightarrow \gamma l_\beta$ with $l_\alpha \neq l_\beta$, occurring as a consequence of the lepton mass matrix changing its orientation (rotating) under changing scales. In this paper, we first discuss these reactions in general terms, then proceed to the calculation of their cross sections in two specific schemes, one within the framework of the conventional Standard Model, the other being the so-called Dualized Standard Model we ourselves advocate. Although the cross section obtained is generally small the calculation reveals certain special circumstances where these reactions may…

PhysicsNuclear and High Energy PhysicsParticle physicsHigh Energy Physics::PhenomenologyFOS: Physical sciencesFísicaType (model theory)Mass matrixStandard ModelOrientation (vector space)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics::ExperimentLepton
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Implications of a Rotating Mass Matrix

2001

The fermion mass matrix, in addition to having eigenvalues (masses) which run, also changes its orientation (rotates) with changing energy scales. This means that its eigenstates at one scale will no longer be eigenstates at another scale, leading to effects where fermions of different flavours can ``transmute'' into one another. In this paper, the implications of a rotating mass matrix are analysed and possible transmuation effects are investigated both in the Standard Model (SM) and in the so-called Dualized Standard Model (DSM) that we advocate, arriving at the conclusion that some transmutational decays such as $\psi \longrightarrow \mu \tau$, $\Upsilon \longrightarrow \mu \tau$ or $\pi…

PhysicsNuclear and High Energy PhysicsParticle physicsScale (ratio)Electron–positron annihilationFísicaFOS: Physical sciencesFermionMass matrixStandard ModelOrientation (vector space)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Energy (signal processing)Eigenvalues and eigenvectors
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High-frequency even harmonics generation in a plasma with electron heat flux

2004

It is shown that in a weakly nonuniform plasma with electron heat flux the generation of odd and even harmonics of high frequency radiation is possible. The even harmonics properties qualitatively differ as compared to those of odd harmonics and depend in an essential way on the heat flux value and orientation with respect to the fundamental wave polarization and propagation directions.

PhysicsNuclear magnetic resonanceHeat fluxOrientation (geometry)HarmonicsGeneral Physics and AstronomyPlasmaElectronHigh frequency radiationComputational physicsPhysics Letters A
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