Search results for "Functional analysis"

showing 10 items of 1059 documents

Thermalization of the dispersive three-wave interaction

2007

We investigate the role of dispersion effects on the long-term evolution of the nonlinear three-wave interaction. We show that the three waves exhibit, as a general rule, an irreversible evolution towards a thermodynamic equilibrium state in which they propagate with identical velocities. As a result of this thermalization process, the three-wave system is driven away from spatio-temporal resonance, so that the equilibrium state does not satisfy the (phase-matching) resonant conditions of energy and momentum conservation for the averaged frequencies. Moreover, we show that the interplay between temporal dispersion and spatial diffraction leads to the emergence of a peculiar equilibrium stat…

PhysicsDiffractionThermodynamic equilibriumGeneral Physics and AstronomyEnergy–momentum relationState (functional analysis)01 natural sciencesResonance (particle physics)010305 fluids & plasmasNonlinear systemThermalisationClassical mechanicsQuantum electrodynamics0103 physical sciences010306 general physicsDispersion (water waves)ComputingMilieux_MISCELLANEOUS
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Fourier-transform spectroscopy and relativistic electronic structure calculation on the c3Σ+ state of KCs

2021

Abstract The Ti:Saphire laser operated within 13800 - 11800 cm − 1 range was used to excite the c 3 Σ + state of KCs molecule directly from the ground X 1 Σ + state. The laser-induced fluorescence (LIF) spectra of the c 3 Σ + → a 3 Σ + transition were recorded with Fourier-transform spectrometer within 8000 to 10000 cm − 1 range. Overall 673 rovibronic term values belonging to both e / f -components of the c 3 Σ + ( Ω = 1 ± ) state of 39 KCs, covering vibrational levels from v = 0 to about 45, and rotational levels J ∈ [ 11 , 149 ] were determined with the accuracy of about 0.01 cm − 1 ; among them 7 values for 41 KCs. The experimental term values with v ∈ [ 0 , 22 ] were involved in a dire…

PhysicsDipoleRadiationCoupled clusterMoleculeElectronic structureState (functional analysis)Atomic physicsPotential energySpectroscopyAtomic and Molecular Physics and OpticsSpectral lineFourier transform spectroscopyJournal of Quantitative Spectroscopy and Radiative Transfer
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Shell-model study of the highly forbidden beta decay 48 Ca → 48 Sc

1999

Ordinary β− decay of the 0+ ground state of 48Ca is studied. Partial half-lives for the highly-forbidden transitions to the three lowest-lying states (6+,5+,4+) of 48Sc are calculated by using both the harmonic oscillator and the Woods-Saxon mean-field wave functions. We find the decay to be dominated, as expected, by the unique fourth-forbidden transition to the excited 5+ state of 48Sc. The theoretical beta-decay half-life of 48Ca is found to be 1.1−0.6+0.8·1021 years which is approximately 25 times longer than the measured double-beta-decay half-life of T1/22ν = (4.3−1.1+2.4[stat] ± 1.4[syst])·1019 years.

PhysicsDouble beta decayExcited stateSHELL modelGeneral Physics and AstronomyState (functional analysis)Atomic physicsGround stateWave functionBeta decayHarmonic oscillatorEurophysics Letters (EPL)
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Permanent electric dipoles andΛ-doubling constants in the lowestΠ1states of RbCs

2005

The article presents first experimental data on the Stark induced $e\text{\ensuremath{-}}f$ mixing in the $(4)\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Pi}$ state of the $^{85}\mathrm{Rb}^{133}\mathrm{Cs}$ molecule, as well as the ab initio calculations of permanent electric dipole moments $(d)$ in the $(1,2,3,4)\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Pi}$ states and $q$ factors in the $(2,4)\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Pi}$ states. The appearance of the ``forbidden'' lines in the laser-induced $(4)\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Pi}\ensuremath{\rightarrow}X\phantom{\rule{0.2em}{0ex}}^{1}\ensuremath{\Pi}^{+}$ fluorescence spectrum in the presence of an elect…

PhysicsElectric dipole momentsymbols.namesakeStark effectAb initio quantum chemistry methodsExcited statesymbolsState (functional analysis)Electronic structurePerturbation theoryAtomic physicsCoupling (probability)Atomic and Molecular Physics and OpticsPhysical Review A
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Evidence of a Resonant Structure in the Cross Section between 4.05 and 4.60 GeV

2019

The cross section of the process e^{+}e^{-}→π^{+}D^{0}D^{*-} for center-of-mass energies from 4.05 to 4.60 GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40 GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6±4.1±6.3  MeV/c^{2} and a width of 77.0±6.8±6.3  MeV, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the Y(4220) state and the theoretical prediction of a D…

PhysicsElectron–positron annihilationDetectorGeneral Physics and AstronomyResonanceState (functional analysis)01 natural sciencesCross section (physics)Amplitude0103 physical sciencesMoleculeAtomic physics010306 general physicsStorage ring
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Triple magnetopolarons in quantum wells

1997

We derive the equations for eigenstates and eigenenergies of a triple magnetopolaron in quantum-well structures. An iteration procedure for obtaining the wave function and energy including the contributions of diagrams with crossing phonon lines is given. We show that under conditions of exact resonance the middle energy branch of the triply split magnetopolaron state consists of only two out of three bare states. We suggest the experimental verification of this prediction.

PhysicsExact resonancePhononQuantum mechanicsHeterojunctionFunction (mathematics)State (functional analysis)Condensed Matter::Mesoscopic Systems and Quantum Hall EffectQuantum wellEnergy (signal processing)Eigenvalues and eigenvectorsPhysical Review B
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Continuum and discrete excitation spectrum of single quantum rings

2005

Photoluminescence and excitation of the photoluminescence spectroscopy has been performed in single InGaAs self-assembled quantum rings embedded in a field effect structure device. To determine their electronic structure, bias-dependent optical transitions have been analyzed both, for individual quantum rings, and for the averaged ensemble. Our results are compared with a theoretical model, and also with results reported by other authors studying similar nanostructures.

PhysicsExcitation spectrumContinuum (measurement)Condensed Matter::OtherOptical transitionSpectrum (functional analysis)Physics::OpticsCondensed Matter::Mesoscopic Systems and Quantum Hall EffectCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsNanostructuresCondensed Matter::Materials ScienceQuantum mechanicsNetwork of excellenceEuropean commissionSingle quantum ringsQuantumPhotoluminescenceExcitation
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Experimental Evidence for Shape Coexistence in 97Sr59 and Implications for the Structure of the Odd-Odd Isotone 98Y

1988

Experimental evidence for shape coexistence in the odd-mass N=59 isotone 97Sr is presented. The ground state and the lowest excited levels of 97Sr are shown to be spherical, whereas a rotational band based on a state at 585 keV has been identified. Three further levels of deformed origin are proposed. Nilsson-orbital assignments are supported by RPA shell-model calculations. These findings lead to a better understanding of the structure of the odd-odd N=59 isotone 98Y.

PhysicsExcited stateIsotoneNuclear TheoryStructure (category theory)State (functional analysis)Atomic physicsGround state
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Resilience of singlet-state extraction against non-optimal resonance conditions

2008

We have recently presented a protocol for extracting the singlet state of two non-interacting high-dimensional spins through post-selection of the internal state of interaction mediators sent in succession [F. Ciccarello et al., arXiv:0710.3855v1]. The scheme requires each mediator's wavevector to obey appropriate resonance conditions. Here we show the robustness of the scheme in the realistic case where such conditions are not sharply fulfilled.

PhysicsFABRY-PEROT-INTERFEROMETERPhysics and Astronomy (miscellaneous)SpinsCondensed matter physicsquantum information theory transport in mesoscopic systemsState (functional analysis)Resonance (particle physics)Robustness (computer science)Quantum mechanicsSCATTERINGWave vectorResilience (materials science)Singlet stateENTANGLEMENT
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Study of the DKK and DKK¯ systems

2017

Using the fixed center approximation to Faddeev equations, we investigate the $DKK$ and $DK\overline{K}$ three-body systems, considering that the $DK$ dynamically generates, through its $I=0$ component, the ${D}_{s0}^{*}(2317)$ molecule. According to our findings, for the $DK\overline{K}$ interaction we find evidence of a state $I({J}^{P})=1/2({0}^{\ensuremath{-}})$ just above the ${D}_{s0}^{*}(2317)\overline{K}$ threshold and around the $D{f}_{0}(980)$ threshold, with mass of about 2833--2858 MeV, made mostly of $D{f}_{0}(980)$. On the other hand, no evidence related to a state from the $DKK$ interaction is found. The state found could be seen in the $\ensuremath{\pi}\ensuremath{\pi}D$ inv…

PhysicsFaddeev equations010308 nuclear & particles physics0103 physical sciencesCenter (category theory)Invariant massState (functional analysis)010306 general physics01 natural sciencesMathematical physicsPhysical Review D
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