Emergence of pygmy dipole resonances: Magic numbers and neutron skins

Journal Article · Mon Aug 15 04:00:00 EDT 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.84.021302· OSTI ID:21596632

Inakura, Tsunenori ^[1]; Nakatsukasa, Takashi ^[1]; Yabana, Kazuhiro ^[2]

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1. RIKEN Nishina Center, Wako, 351-0198 (Japan)
2. Center for Computational Sciences, University of Tsukuba, Tsukuba 305-8571 (Japan)

The pygmy dipole resonances (PDR) for even-even nuclei in 8{<=}Z{<=}40 are studied performing a systematic calculation of the random-phase approximation with the Skyrme functional of SkM*. The calculation is fully self-consistent and does not assume any symmetry in the nuclear shape of the ground state. In every isotopic chain, the PDR emerges by showing a peak of the E1 strength at energies less than 10 MeV. The E1 strength of the PDR strongly depends on the position of the Fermi level and shows a clear correlation with the occupation of the orbits with the orbital angular momenta less than 3({h_bar}/2{pi}) (l{<=}2). We also found a strong correlation between the isotopic dependence of the neutron skin thickness and the pygmy dipole strength. The fraction of the energy-weighted strength exhausted by the PDR and the neutron skin thickness show a linear correlation with the universal rate of about 0.2 fm{sup -1}.

• OSTI ID: 21596632
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 2 Vol. 84; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANGULAR MOMENTUM
APPROXIMATIONS
BARYONS
CALCULATION METHODS
COMPUTERIZED SIMULATION
CORRELATIONS
DIMENSIONS
DIPOLES
ELEMENTARY PARTICLES
ENERGY LEVELS
ENERGY RANGE
EVEN-EVEN NUCLEI
FERMI LEVEL
FERMIONS
GROUND STATES
HADRONS
MAGIC NUCLEI
MEV RANGE
MEV RANGE 01-10
MULTIPOLES
NEUTRONS
NUCLEI
NUCLEON-NUCLEON POTENTIAL
NUCLEONS
OCCUPATIONS
ORBITAL ANGULAR MOMENTUM
ORBITS
POTENTIALS
RANDOM PHASE APPROXIMATION
RESONANCE
SIMULATION
SKYRME POTENTIAL
SYMMETRY
THICKNESS