Search results for "Cluster Model"

showing 3 items of 3 documents

The integral‐direct coupled cluster singles and doubles model

1996

An efficient and highly vectorized implementation of the coupled cluster singles and doubles (CCSD) model using a direct atomic integral technique is presented. The minimal number of n6processes has been implemented for the most time consuming terms and point group symmetry is used to further reduce operation counts and memory requirements. The significantly increased application range of the CCSD method is illustrated with sample calculations on several systems with more than 500 basis functions. Furthermore, we present the basic trends of an open ended algorithm and discuss the use of integral prescreening. © 1996 American Institute of Physics.

Computer scienceClose Coupling ApproximationSymmetry GroupsGeneral Physics and AstronomyBasis functionSymmetry groupUNESCO::FÍSICA::Química físicaComputational scienceCluster ModelClose Coupling Approximation ; Algorithms ; Cluster Model ; Electronic Structure ; Molecular Orbital Method ; Symmetry GroupsPhysics and Astronomy (all)Range (mathematics)Coupled clusterElectronic StructureComputational chemistryCluster (physics)Molecular symmetryMolecular Orbital MethodPhysical and Theoretical Chemistry:FÍSICA::Química física [UNESCO]Direct-coupled amplifierAlgorithmsThe Journal of Chemical Physics
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Neutron halos in the excited states of B12

2018

The differential cross sections of the $^{11}\mathrm{B}(d,p)\phantom{\rule{0.16em}{0ex}}^{12}\mathrm{B}$ reaction leading to formation of the ${1}^{+}$ ground state and the 0.95-MeV ${2}^{+}$, 1.67-MeV ${2}^{\ensuremath{-}}$, 2.62-MeV ${1}^{\ensuremath{-}}$, 2.72-MeV ${0}^{+}$, and 3.39-MeV ${3}^{\ensuremath{-}}$ excited states of $^{12}\mathrm{B}$ are measured at ${E}_{d}$ = 21.5 MeV. The analysis of the data is carried out within the coupled-reaction-channels method for the direct neutron transfer and the Hauser-Feshbach formalism of the statistical compound-nucleus model. The spectroscopic factors, asymptotic normalization coefficients, and rms radii of the last neutron in all states stu…

Physicsta114electromagnetic moments010308 nuclear & particles physicsNuclear Theorynucleon distributiondirect reactions01 natural sciencescluster modelsExcited state0103 physical sciencesbooritransfer reactionsPhysics::Accelerator PhysicsNeutronspectroscopic factorsHaloAtomic physicsydinfysiikkaNuclear Experiment010306 general physicsGround statePhysical Review C
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Neutron halos in the excited states of 12B

2018

The differential cross sections of the 11B(d,p) 12B reaction leading to formation of the 1+ ground state and the 0.95-MeV 2+, 1.67-MeV 2−, 2.62-MeV 1−, 2.72-MeV 0+, and 3.39-MeV 3− excited states of 12B are measured at Ed = 21.5 MeV. The analysis of the data is carried out within the coupled-reaction-channels method for the direct neutron transfer and the Hauser-Feshbach formalism of the statistical compound-nucleus model. The spectroscopic factors, asymptotic normalization coefficients, and rms radii of the last neutron in all states studied are deduced. The existence of the neutron halos in the 1.67-MeV 2− and 2.62-MeV 1− states is found, consistent with the earlier published data. New in…

cluster modelselectromagnetic momentsNuclear Theorynucleon distributiontransfer reactionsbooriPhysics::Accelerator Physicsspectroscopic factorsdirect reactionsNuclear Experimentydinfysiikka
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