Isospin Character of the Pygmy Dipole Resonance in 124Sn

Abstract

The pygmy dipole resonance has been studied in the proton-magic nucleus 124Sn with the (a,a'g) coincidence method at E=136 MeV. The comparison with results of photon-scattering experiments reveals a splitting into two components with different structure: one group of states which is excited in (a,a'g) as well as in (g,g') reactions and a group of states at higher energies which is only excited in (g,g') reactions. Calculations with the self-consistent relativistic quasiparticle time-blocking approximation and the quasiparticle phonon model are in qualitative agreement with the experimental results and predict a low-lying isoscalar component dominated by neutron-skin oscillations and a higher-lying more isovector component on the tail of the giant dipole resonance.

References in corpus (8)

• Exotic modes of excitation in atomic nuclei far from stability
• Constraints on the symmetry energy and on neutron skins from the pygmy resonances in 68Ni and 132Sn
• Pygmy dipole resonance as a constraint on the neutron skin of heavy nuclei
• Investigation of Pygmy Dipole Resonances in the Tin Region
• Relativistic quasiparticle time blocking approximation. Dipole response of open-shell nuclei
• Pygmy dipole strength in 90Zr
• Relativistic quasiparticle time blocking approximation. II. Pygmy dipole resonance in neutron-rich nuclei
• Decay Pattern of Pygmy States Observed in Neutron-Rich 26 Ne

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