Search results for "DIPOLE"

showing 10 items of 982 documents

Dipole sum rule enhancement in nuclei

2008

In this work we apply a microscopic many-body approach to photonuclear reactions[1] in order to improve the understanding of the dipole sum rule. At the same time, the sum rule provides us with test of consistency of the underlying theory at low photon energies

PhysicsDipoleWork (thermodynamics)PhotonConsistency (statistics)Quantum mechanicsRule of sumOrder (ring theory)Sum rule in quantum mechanics
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Line strengths of the ν2 + ν3 and ν3 − ν2 bands of methane (12CH4)

1992

Abstract The individual linestrengths of two related bands of 12 CH 4 , ν 2 + ν 3 near 4545 cm −1 and ν 3 − ν 2 near 1484 cm −1 , were measured with accuracies of 3% and 5%, respectively. In the analysis, an eight-term expansion of the dipole moment through second order was required to fit the strengths of transitions up to J ′ = 10 in ν 2 + ν 3 and J ′ = 12 in ν 3 − ν 2 and to explain the considerable perturbations observed. Application of this model reduced the rms deviations from 68% (zero-order) to 6.3% with the 248 selected lines of ν 2 + ν 2 and from 37% to 5.8% with 186 lines of ν 3 − ν 2 . The integrated bandstrengths for the two bands, respectively, are 1.84(5) and 0.0085(4) cm −2 …

PhysicsDipolechemistry.chemical_compoundNuclear magnetic resonancechemistryAbsorption spectroscopyInfraredAnalytical chemistryPhysical and Theoretical ChemistrySpectroscopyAtomic and Molecular Physics and OpticsMethaneLine (formation)Journal of Molecular Spectroscopy
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Controlled insertion of one and two atoms into a high-finesse optical cavity

2007

Entangled quantum states have applications as a model system for strongly correlated many body states, as resource for quantum information processing and as a tool for enhanced precision measurements. Deterministic entanglement schemes create the desired state by transferring the system under the action of a carefully chosen Hamiltonian into an entangled state. The system must follow a unitary evolution, and uncontrolled parasitic interactions with the environment leading to spontaneous decay or partial measurements of the state have to be avoided. The paper present an experiment, on loading a chosen number of Doppler-cooled caesium atoms from a magneto-optical trap into a standing wave opt…

PhysicsDipolelawQuantum dotQuantum stateOptical cavityMagneto-optical trapAtomAtom opticsPhysics::Atomic PhysicsQuantum entanglementAtomic physicslaw.invention
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Calculated rJ2-type effective dipole moment parameters for fundamental bands of tetrahedral XY4 molecules

1991

Abstract Formulas in terms of basic molecular constants are presented for effective dipole moment parameters which are responsible for second-order corrections to the line intensities of fundamental bands of tetrahedral XY 4 molecules. Two cases have been considered. In the first case all bands were considered as separate bands. In the second case the ν 2 and ν 4 bands were considered as interacting bands. The influence of effective Hamiltonian transformations on effective dipole moment parameters has been studied. Numerical calculations of effective dipole moment parameters for the ν 2 and ν 4 bands of 12 CH 4 have been performed. There is reasonable agreement between calculated and fitted…

PhysicsDipolesymbols.namesakeCondensed matter physicsTransition dipole momentTetrahedronsymbolsMoleculePhysical and Theoretical ChemistryAtomic physicsHamiltonian (quantum mechanics)SpectroscopyAtomic and Molecular Physics and OpticsJournal of Molecular Spectroscopy
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Solvation of triplet Rydberg states of molecular hydrogen in superfluid helium

2004

We report ab initio interaction potentials, transition dipole moments, and radiative lifetimes for the four lowest triplet states of ${\mathrm{H}}_{2}:$ $b$ ${}^{3}{\ensuremath{\Sigma}}_{u}^{+},$ $c$ ${}^{3}{\ensuremath{\Pi}}_{u},$ $a$ ${}^{3}{\ensuremath{\Sigma}}_{g}^{+},$ and $e$ ${}^{3}{\ensuremath{\Sigma}}_{u}^{+},$ and their response to the perturbation due to approaching ground state He atom. Hybrid density functional\char21{}quantum Monte Carlo calculations employing the ab initio interaction potentials are then used for calculating the liquid structure around the molecular excimers in bulk superfluid ${}^{4}\mathrm{He}.$ Calculations demonstrate a wide variety of possible solvation …

PhysicsDipolesymbols.namesakeHelium-4Absorption spectroscopyQuantum Monte CarloMetastabilityAb initioRydberg formulasymbolsAtomic physicsGround stateAtomic and Molecular Physics and OpticsPhysical Review A
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Multipole solitary wave solutions of the higher-order nonlinear Schrödinger equation with quintic non-Kerr terms

2013

We consider a high-order nonlinear Schrodinger (HNLS) equation with third- and fourth-order dispersions, quintic non-Kerr terms, self steepening, and self-frequency-shift effects. The model applies to the description of ultrashort optical pulse propagation in highly nonlinear media. We propose a complex envelope function ansatz composed of single bright, single dark and the product of bright and dark solitary waves that allows us to obtain analytically different shapes of solitary wave solutions. Parametric conditions for the existence and uniqueness of such solitary waves are presented. The solutions comprise fundamental solitons, kink and anti-kink solitons, W-shaped, dipole, tripole, and…

PhysicsDirect numerical simulationAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsQuintic functionDipoleNonlinear systemsymbols.namesakeNonlinear Sciences::Exactly Solvable and Integrable SystemsClassical mechanicssymbolsUniquenessElectrical and Electronic EngineeringPhysical and Theoretical ChemistryMultipole expansionNonlinear Sciences::Pattern Formation and SolitonsNonlinear Schrödinger equationAnsatzOptics Communications
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top data system (TDS) software for spectrum simulation of asymmetric molecules

2005

Abstract The D 2 h TDS ( D 2 h Top Data System) program suite has been developed with the aim of studying any rovibrational band or polyad of X 2 Y 4 ( D 2 h ) asymmetric top molecules. It is based on the same principles as similar programs from our group already released for various molecular symmetries ( T d , O h , C 4 v , C 2 v ). We work in the O ( 3 ) ⊃ D 2 h chain and this choice has consequences on the method used to specify the input parameters of the programs for Hamiltonian and transition moment calculations. Two examples concerning the ν 12 and ν 2 bands of the C 2 H 4 molecule are presented. This suite consists of a series of FORTRAN programs called by a script. The whole packa…

PhysicsDiscrete mathematicsRadiationFortranbusiness.industryTransition dipole momentRotational–vibrational spectroscopyAtomic and Molecular Physics and Opticssymbols.namesakeSoftwareHomogeneous spacesymbolsMoleculeHamiltonian (quantum mechanics)businesscomputerSpectroscopycomputer.programming_languageJournal of Quantitative Spectroscopy and Radiative Transfer
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Calculation of atomic spectra and transition amplitudes for superheavy element Db (Z=105)

2018

Atomic spectra and other properties of superheavy element dubnium (Db, $Z=105$) are calculated using recently developed method combining configuration interaction with perturbation theory [the CIPT method, V. A. Dzuba, J. C. Berengut, C. Harabati, and V. V. Flambaum, Phys. Rev. A 95, 012503 (2017)]. These include energy levels for low-lying states of Db and Db II, electric dipole transition amplitudes between the ground state and low-lying states of opposite parity, isotope shift for these transitions, and the ionization potential of Db. Similar calculations for Ta, which is a lighter analog of Db, are performed to control the accuracy of the calculations.

PhysicsDubniumAtomic Physics (physics.atom-ph)FOS: Physical scienceschemistry.chemical_elementConfiguration interaction7. Clean energy01 natural sciences010305 fluids & plasmasPhysics - Atomic PhysicsAmplitudechemistry0103 physical sciencesPhysics::Atomic PhysicsNuclear Experiment (nucl-ex)Atomic physicsElectric dipole transitionIonization energyPerturbation theory010306 general physicsGround stateSpectroscopyNuclear Experiment
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Isospin Character of Low-Lying Pygmy Dipole States inPb208via Inelastic Scattering ofO17Ions

2014

The properties of pygmy dipole states in Pb-208 were investigated using the Pb-208(O-17, O-17'gamma) reaction at 340 MeV and measuring the gamma decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted gamma rays and of the scattered particles were measured. The results are compared with (gamma, gamma') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2(+) and 3(-) states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first t…

PhysicsElastic scatteringDipoleAstrophysics::High Energy Astrophysical PhenomenaIsospinIsoscalarGamma rayGeneral Physics and AstronomyAGATABorn approximationAtomic physicsInelastic scattering7. Clean energyPhysical Review Letters
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Coherent Spin Dependent Landau-Zener Tunneling in Mixed Valence Dimers

2011

In this contribution we introduce the concept of single molecule ferroelectric based on the vibronic pseudo Jahn-Teller model of mixed valence dimeric clusters belonging to the Robin and Day class II compounds. We elucidate the main factors controlling the nonadiabatic Landau-Zener tunneling between the low lying vibronic levels induced by a pulse of the electric field. The transition probabilities are shown to be dependent on the both time of the pulse and the total spin of the cluster. A possibility to control the spin-dependent Landau-Zener tunneling by applying a static magnetic field is discussed.

PhysicsElectric dipole momentValence (chemistry)Condensed matter physicsElectric fieldCluster (physics)Condensed Matter::Strongly Correlated ElectronsPhysics::Chemical PhysicsCondensed Matter::Mesoscopic Systems and Quantum Hall EffectMagnetostaticsFerroelectricityQuantum tunnellingQuantum dimer models
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