# Pygmy and core polarization dipole modes in 206Pb: Connecting nuclear structure to stellar nucleosynthesis

@article{Tonchev2017PygmyAC,
title={Pygmy and core polarization dipole modes in 206Pb: Connecting nuclear structure to stellar nucleosynthesis},
author={Anton P. Tonchev and N. Tsoneva and Chitra Bhatia and C. W. Arnold and Stephane Goriely and S. L. Hammond and J. H. Kelley and Elaine Kwan and H. Lenske and Jorge Piekarewicz and Rajarshi Raut and Gencho Y. Rusev and Toshiyuki Shizuma and Werner Tornow},
journal={Physics Letters B},
year={2017},
volume={773},
pages={20-25}
}
Abstract A high-resolution study of the electromagnetic response of 206Pb below the neutron separation energy is performed using a ( γ → , γ ′ ) experiment at the HI γ → S facility. Nuclear resonance fluorescence with 100% linearly polarized photon beams is used to measure spins, parities, branching ratios, and decay widths of excited states in 206Pb from 4.9 to 8.1 MeV. The extracted Σ B ( E 1 ) ↑ and Σ B ( M 1 ) ↑ values for the total electric and magnetic dipole strength below the neutron… Expand
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#### References

SHOWING 1-10 OF 83 REFERENCES
The pygmy quadrupole resonance and neutron-skin modes in Sn-124
We present an extensive experimental study of the recently predicted pygmy quadrupole resonance (PQR) in Sn isotopes, where complementary probes were used. In this study, (alpha,alpha 'gamma) andExpand
Pygmy resonances and radiative nucleon captures for stellar nucleosynthesis
• Physics
• 2015
The impact of low-energy multipole excitations and pygmy resonances on radiative neutron and proton-capture cross sections in nuclei close to the β-stability line is investigated. For this purpose, aExpand
Photoneutron cross sections of 208Pb and 197Au
• Physics
• 1970
Abstract Partial photoneutron cross sections σ γ , n , σ γ , 2 n , σ γ , 3 n and σ γ ·4 n of 208 Pb and 197 Au were measured using a monochromatic photon beam and a neutron detecting system capableExpand
Isospin properties of electric dipole excitations in 48Ca
Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus Ca-48 below the neutron threshold. Real-photon scattering experiments usingExpand
Investigation of Pygmy Dipole Resonances in the Tin Region
• Physics
• 2008
The evolution of the low-energy electromagnetic dipole response with the neutron excess is investigated along the Sn isotopic chain within an approach incorporating Hartree-Fock-Bogoljubov (HFB) andExpand
Emergence of pygmy dipole resonances: Magic numbers and neutron skins
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*. TheExpand
Complete electric dipole response and the neutron skin in 208Pb.
The extracted E1 polarizability leads to a neutron skin thickness close to that of a neutron star, thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars. Expand
Pygmy dipole resonance as a constraint on the neutron skin of heavy nuclei
The isotopic dependence of the isovector Pygmy dipole response in tin is studied within the framework of the relativistic random-phase approximation. Regarded as an oscillation of the neutron skinExpand
Nuclear deformation and neutron excess as competing effects for dipole strength in the pygmy region.
A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides. Expand
Probing the nuclear neutron skin by low-energy dipole modes
• Physics
• 2004
Abstract Dipole excitations below the neutron threshold in neutron-rich Sn isotopes are studied theoretically in the Quasiparticle–Phonon Model with Hartree–Fock–Bogoliubov single-particle input. OfExpand