Search results for "Model parameters"

showing 10 items of 37 documents

High Field Polarization Response in Ferroelectrics: Current Solutions and Challenges

2006

Polarization response including ergodicity breaking and the divergence of relaxation time is reproduced for model Hamiltonians of growing complexity. Systematic derivation of the dynamical equations and its solutions is based on the Fokker-Planck and imaginary time Schrödinger equation techniques with subsequent symplectic integration. Test solutions are addressed to finite size and spatially extended problems with microscopically interpretation of the model parameters as a challenge.

PhysicsMechanical EngineeringErgodicityModel parametersCondensed Matter PhysicsPolarization (waves)Imaginary timeSchrödinger equationsymbols.namesakeMechanics of MaterialsQuantum mechanicssymbolsGeneral Materials ScienceStatistical physicsSymplectic integratorHigh fieldEquations for a falling bodyMaterials Science Forum
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RChL currents in Tauola: implementation and fit parameters

2013

We present the results of a partial upgrade to the Monte Carlo event generator TAUOLA using Resonance Chiral Theory for the two and three meson final states. These modes account for 88% of total hadronic width of the tau meson. The first results of the model parameters have been obtained using Preliminary BaBar data for the three pion mode.

PhysicsNuclear and High Energy PhysicsParticle physicsMesonHigh Energy Physics::LatticeNuclear TheoryHigh Energy Physics::PhenomenologyMonte Carlo methodHadronMode (statistics)FOS: Physical sciencesModel parametersResonance (particle physics)Atomic and Molecular Physics and OpticsHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)UpgradeHigh Energy Physics::ExperimentNuclear ExperimentParticle Physics - PhenomenologyEvent generatorNuclear Physics B - Proceedings Supplements
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Form factors for semileptonic, nonleptonic, and rareB(Bs)meson decays

2012

We provide new values for the model parameters of the covariant constituent quark model (with built–in infrared confinement) in the meson sector by a fit to the leptonic decay constants and a number of electromagnetic decays. We then evaluate, in a parameter-free way, the form factors of the B(Bs) ! P(V ) transitions in the full kinematical region of momentum transfer. As an application of our results we calculate the widths of the nonleptonic Bs-decays into Ds D + , D � s D + s +D s D � + s

PhysicsNuclear and High Energy PhysicsParticle physicsMesonInfraredHigh Energy Physics::PhenomenologyMomentum transferForm factor (quantum field theory)Constituent quarkModel parametersNuclear physicsCP violationHigh Energy Physics::ExperimentCovariant transformationPhysical Review D
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Search for massive, long-lived particles using multitrack displaced vertices or displaced lepton pairs inppcollisions ats=8  TeVwith the ATLAS detect…

2015

Many extensions of the Standard Model posit the existence of heavy particles with long lifetimes. This article presents the results of a search for events containing at least one long-lived particle that decays at a significant distance from its production point into two leptons or into five or more charged particles. This analysis uses a data sample of proton-proton collisions at root s = 8 TeV corresponding to an integrated luminosity of 20.3 fb(-1) collected in 2012 by the ATLAS detector operating at the Large Hadron Collider. No events are observed in any of the signal regions, and limits are set on model parameters within supersymmetric scenarios involving R-parity violation, split sup…

PhysicsNuclear and High Energy PhysicsParticle physicsSplit supersymmetryLarge Hadron ColliderAtlas (topology)Atlas detectorScatteringHigh Energy Physics::PhenomenologyModel parametersCharged particleNuclear physicsHigh Energy Physics::ExperimentLeptonPhysical Review D
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Bs,d0→ℓ+ℓ− Decays in Two-Higgs Doublet Models

2016

Abstract We study the rare leptonic decays B s , d 0 → l + l − within the general framework of the aligned two-Higgs doublet model [1]. A complete one-loop calculation of the relevant short-distance Wilson coefficients is presented, with a detailed technical summary of the results. The phenomenological constraints imposed by present data on the model parameters are also investigated.

PhysicsNuclear and High Energy PhysicsTwo-Higgs-doublet modelParticle physics010308 nuclear & particles physicsPhysics beyond the Standard ModelHigh Energy Physics::Phenomenology0103 physical sciencesHiggs bosonModel parameters010306 general physics01 natural sciencesNuclear and Particle Physics Proceedings
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$ B_{s,d}^0 $ → ℓ + ℓ − decays in the aligned two-Higgs-doublet model

2014

The rare decays $B_{s,d}^0 \to \ell^+\ell^-$ are analyzed within the general framework of the aligned two-Higgs doublet model. We present a complete one-loop calculation of the relevant short-distance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We investigate the impact of various model parameters on the branching ratios and study the phenomenological constraints imposed by present data.

PhysicsNuclear and High Energy PhysicsTwo-Higgs-doublet modelParticle physicsFísicaModel parametersJournal of High Energy Physics
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Relative efficiency revealed: Equations for k<inf>1</inf>–k<inf>6</inf> of the PVGIS model

2014

The European PV Geographical Information System (PVGIS) describes module performance in terms of the relative efficiency with respect to Standard Testing Conditions (STC). The efficiency's dependence on irradiance and operating temperature is modeled with a bi-quadratic polynomial with respect to the relative temperature and the logarithm of relative irradiance. In earlier works, the present author derived relations between two model coefficients describing the irradiance dependence at 25°C, k 1 and k 2 , and I–V curve model parameters such as the series resistance RS and the ideality factor n. There was good agreement between the theoretical and fitted values of k 1 , but the fitted values…

PolynomialEfficiencyLogarithmOperating temperatureEquivalent series resistancebusiness.industryMathematical analysisElectrical engineeringIrradianceModel parametersbusinessPerformance modelMathematics2014 IEEE 40th Photovoltaic Specialist Conference (PVSC)
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Traveling Waves Emerging in a Diffusive Moving Filament System

2014

Starting from a minimal model for the actin cytoskeleton of motile cells we derive a spatially one dimensional model describing populations of right and left moving filaments with intrinsic velocity, diffusion and mutual alignment. For this model we derive traveling wave solutions whose speed and shape depend on the model parameters and the type of alignment. We discuss possible wave profiles obtained from analytical investigations as well as waves emerging in numerical simulations. In particular, we will explicitly comment on the observed wave speeds and how they are related to the model parameters. Moreover, some particularly interesting patterns being composed of several wave profiles ar…

Protein filamentMinimal modelPhysicsClassical mechanicsTraveling waveModel parametersDiffusion (business)Type (model theory)CytoskeletonActin cytoskeletonQuantitative Biology::Cell Behavior
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From pseudo-bosons to pseudo-Hermiticity via multiple generalized Bogoliubov transformations

2016

We consider the special type of pseudo-bosonic systems that can be mapped to standard bosons by means of generalized Bogoliubov transformation and demonstrate that a pseudo-Hermitian systems can be obtained from them by means of a second subsequent Bogoliubov transformation. We employ these operators in a simple model and study three different types of scenarios for the constraints on the model parameters giving rise to a Hermitian system, a pseudo-Hermitian system in which the second the Bogoliubov transformations is equivalent to the associated Dyson map and one in which we obtain D-quasi bases.

Pseudo-bosonSwanson modelFOS: Physical sciencesModel parametersPT-symmetry01 natural sciences0103 physical sciences010306 general physicsSettore MAT/07 - Fisica MatematicaMathematical PhysicsQCBosonMathematical physicsPhysicsCondensed Matter::Quantum GasesQuantum Physics010308 nuclear & particles physicsStatistical and Nonlinear PhysicsMathematical Physics (math-ph)Condensed Matter PhysicsHermitian matrixFormalism (philosophy of mathematics)Bogoliubov transformationpseudo-HermiticityQuantum Physics (quant-ph)Statistical and Nonlinear Physic
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Estimating radiant fields in flat heterogeneous photoreactors by the six-flux model

2006

Heterogeneous photoreactor modeling is a task complicated by the integro-differential nature of the Radiation Transfer Equation (RTE) when scattering phenomena are important. In the present work, a novel “Six Flux Model” (SFM) is proposed, which may be regarded as a step forward with respect to the previously proposed “Two Flux Model” (TFM). In order to validate the newly proposed model, Monte Carlo simulations of an indefinite plane-slab photoreactor have been performed. As no simplifying assumptions are involved in this case, the information obtained may be regarded as “pseudo-experimental,” and therefore compared with the predictions of both TFM and SFM models. Results show that the nove…

SIX-FLUX MODELEngineeringWork (thermodynamics)Environmental EngineeringScatteringbusiness.industryGeneral Chemical EngineeringSettore ING-IND/25 - Impianti ChimiciRADIANT FIELDMonte Carlo methodFluxModel parametersHETEROGENEOUS PHOTOREACTORTWO-FLUX MODELRadiation transferExact solutions in general relativityMONTE CARLOApplied mathematicsbusinessTransfer equationSimulationBiotechnology
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