0000000000509222

AUTHOR

Koichi Sato

showing 8 related works from this author

Isospin-invariant Skyrme energy-density-functional approach with axial symmetry

2014

We develop the isospin-invariant Skyrme-EDF method by considering local densities in all possible isospin channels and proton-neutron (p-n) mixing terms as mandated by the isospin symmetry. The EDF employed has the most general form that depends quadratically on the isoscalar and isovector densities. We test and benchmark the resulting p-n EDF approach, and study the general properties of the new scheme by means of the cranking in the isospin space. We extend the existing axial DFT solver HFBTHO to the case of isospin-invariant EDF approach with all possible p-n mixing terms. Explicit expressions have been derived for all the densities and potentials that appear in the isospin representatio…

PhysicsNuclear and High Energy PhysicsIsovectorNuclear Theoryta114IsoscalarNuclear TheoryFOS: Physical sciencesSolverNuclear Theory (nucl-th)isospintiheysIsospinPairingQuantum electrodynamicsQuantum mechanicsCoulombSymmetry breakingAxial symmetryNuclear ExperimentPhysical review C
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Isospin-symmetry breaking in masses of ≃ Nuclei

2018

Effects of the isospin-symmetry breaking (ISB) beyond mean-field Coulomb terms are systematically studied in nuclear masses near the N=Z line. The Coulomb exchange contributions are calculated exactly. We use extended Skyrme energy density functionals (EDFs) with proton–neutron-mixed densities, to which we add new terms breaking the isospin symmetry. Two parameters associated with the new terms are determined by fitting mirror and triplet displacement energies (MDEs and TDEs) of isospin multiplets. The new EDFs reproduce MDEs for the T=12 doublets and T=1 triplets, and TDEs for the T=1 triplets. Relative strengths of the obtained isospin-symmetry-breaking terms are not consistent with the d…

Nuclear and High Energy PhysicsParticle physicsprotonitNuclear TheoryTriplet displacement energy (TDE)01 natural sciencesComputer Science::Digital LibrariesDisplacement (vector)Energy density functional (EDF)Proton–neutron mixingproton–neutron mixingnuclear physicstiheysmirror displacement energy (MDE)0103 physical sciencesCoulombSymmetry breaking010306 general physicsnuclear density functional theory (DFT)density functional theoryLine (formation)Physicsdensityenergiata114protons010308 nuclear & particles physicsScatteringtiheysfunktionaaliteorianeutronsneutronitenergy density functional (EDF)lcsh:QC1-999Symmetry (physics)Isospin symmetry breaking (ISB)Isospintriplet displacement energy (TDE)isospin symmetry breaking (ISB)ydinfysiikkaMirror displacement energy (MDE)Parametrizationlcsh:PhysicsenergyPhysics Letters
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Solution of the Skyrme-Hartree–Fock–Bogolyubovequations in the Cartesian deformed harmonic-oscillator basis. (VIII) hfodd (v2.73y): A new version of …

2017

We describe the new version (v2.73y) of the code HFODD which solves the nuclear Skyrme Hartree-Fock or Skyrme Hartree-Fock-Bogolyubov problem by using the Cartesian deformed harmonic-oscillator basis. In the new version, we have implemented the following new features: (i) full proton-neutron mixing in the particle-hole channel for Skyrme functionals, (ii) the Gogny force in both particle-hole and particle-particle channels, (iii) linear multi-constraint method at finite temperature, (iv) fission toolkit including the constraint on the number of particles in the neck between two fragments, calculation of the interaction energy between fragments, and calculation of the nuclear and Coulomb ene…

Angular momentumNuclear Theory[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th]SYMMETRYNuclear TheoryHartree–Fock methodGeneral Physics and AstronomyFOS: Physical sciencesGogny forceSkyrme interactionNuclear density functional theorySelf-consistent mean-field01 natural sciences114 Physical sciencesNuclear Theory (nucl-th)Energy density functional theorySYSTEMSQuantum mechanics0103 physical sciences010306 general physicsHarmonic oscillator[ PHYS.NUCL ] Physics [physics]/Nuclear Theory [nucl-th]PhysicsHartree–Fock–Bogolyubovta114010308 nuclear & particles physicsAugmented Lagrangian methodInteraction energyAngular-momentum projection113 Computer and information sciencesHardware and ArchitecturePairingIsospintheoretical nuclear physicsSelf-consistent mean fieldHartree-Fock-BogolyubovPairing correlations
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Energy-density-functional calculations including the proton-neutron mixing

2013

We present results of calculations based on the Skyrme energy density functional including the arbitrary mixing between protons and neutrons. In this framework, single-particle states are superpositions of proton and neutron components and the energy density functional is fully invariant with respect to three-dimensional rotations in the isospin space. The isospin of the system is controlled by means of the isocranking method, which carries over the standard cranking approach to the isospin space. We show numerical results of the isocranking calculations performed for isobaric analogue states in the A=14 and $A=40-56$ nuclei. We also present such results obtained for high-isospin states in …

PhysicsNuclear and High Energy PhysicsParticle physicsNuclear Theoryta114ProtonEnergy density functionalNuclear TheoryFOS: Physical sciencesInvariant (physics)Nuclear physicsNuclear Theory (nucl-th)symbols.namesakeIsospinLagrange multipliersymbolsIsobaric processNeutronNuclear ExperimentNuclear theory
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Mean-Field Calculation Based on Proton-Neutron Mixed Energy Density Functionals

2015

We have performed calculations based on the Skyrme energy density functional (EDF) that includes arbitrary mixing between protons and neutrons. In this framework, single-particle states are generalized as mixtures of proton and neutron components. The model assumes that the Skyrme EDF is invariant under the rotation in isospin space and the Coulomb force is the only source of the isospin symmetry breaking. To control the isospin of the system, we employ the isocranking method, which is analogous to the standard cranking approach used for describing high-spin states. Here, we present results of the isocranking calculations performed for the isobaric analog states in A = 40 and A = 54 nuclei.

Physicsta114Proton010308 nuclear & particles physicsNuclear TheoryInvariant (physics)01 natural sciencesenergy density functionalsCoulomb's lawNuclear physicssymbols.namesakeMean field theoryproton-neutron mixingisobaric analog statesQuantum electrodynamicsIsospin0103 physical sciencessymbolsIsobaric processNeutronSymmetry breakingNuclear Experiment010306 general physicsProceedings of the Conference on Advances in Radioactive Isotope Science (ARIS2014)
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Mirror and triplet displacement energies within nuclear DFT: : numerical stability

2017

Isospin-symmetry-violating class II and III contact terms are introduced into the Skyrme energy density functional to account for charge dependence of the strong nuclear interaction. The two new coupling constants are adjusted to available experimental data on triplet and mirror displacement energies, respectively. We present preliminary results of the fit, focusing on its numerical stability with respect to the basis size.

Nuclear TheorySYMMETRYNuclear TheoryFOS: Physical sciencesGeneral Physics and Astronomy114 Physical sciences01 natural sciencesDisplacement (vector)strong nuclear forceNuclear Theory (nucl-th)0103 physical sciences010306 general physicsdisplacement energiesdensity functional theoryPARAMETRIZATIONCoupling constantPhysicsta114Energy density functionalBasis (linear algebra)010308 nuclear & particles physicstiheysfunktionaaliteoriaCharge (physics)Nuclear interactionnuclear structureAtomic physicsisospin-symmetry breakingNumerical stability
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Isospin-symmetry breaking in masses of $N\simeq Z$ nuclei

2017

Effects of the isospin-symmetry breaking (ISB) beyond mean-field Coulomb terms are systematically studied in nuclear masses near the $N=Z$ line. The Coulomb exchange contributions are calculated exactly. We use extended Skyrme energy density functionals (EDFs) with proton-neutron-mixed densities, to which we add new terms breaking the isospin symmetry. Two parameters associated with the new terms are determined by fitting mirror and triplet displacement energies (MDEs and TDEs) of isospin multiplets. The new EDFs reproduce MDEs for the $T=\frac12$ doublets and $T=1$ triplets, and TDEs for the $T=1$ triplets. Relative strengths of the obtained isospin-symmetry-breaking terms {\em are not} co…

Nuclear Theory (nucl-th)Nuclear TheoryNuclear TheoryFOS: Physical sciences
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Mean-Field Calculation Based on Proton-Neutron Mixed Energy Density Functionals

2014

We have performed calculations based on the Skyrme energy density functional (EDF) that includes arbitrary mixing between protons and neutrons. In this framework, single-particle states are generalized as mixtures of proton and neutron components. The model assumes that the Skyrme EDF is invariant under the rotation in isospin space and the Coulomb force is the only source of the isospin symmetry breaking. To control the isospin of the system, we employ the isocranking method, which is analogous to the standard cranking approach used for describing high-spin states. Here, we present results of the isocranking calculations performed for the isobaric analog states in $A = 40$ and $A = 54$ nuc…

Nuclear Theory (nucl-th)Nuclear Theoryproton-neutron mixingisobaric analog statesNuclear TheoryFOS: Physical sciencesNuclear Experimentenergy density functionals
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