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arXiv · 1809.02247

Excitation spectra of exotic nuclei in a self-consistent phonon-coupling model

N. Lyutorovich·V. Tselyaev·J. Speth·P. -G. Reinhard
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Abstract

We explore giant resonance spectra and low-lying dipole strength in the Ni and Sn chains from proton rich to very neutron rich isotopes, relevant in astrophysical reaction chains. For the theoretical description we employ the random-phase approximation (RPA) plus many-body effects through a phonon coupling model with optimized selection of phonons. The nuclear force is based on the Skyrme-Hartree-Fock energy functional carried consistently through all steps of modelling. The main effect of phonon coupling is a broadening of the spectral distributions (collisional width). This broadening is particularly dramatic for low-lying dipole strength in very neutron rich nuclei delivering there a qualitative change of the spectra.

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N. Lyutorovich, V. Tselyaev, J. Speth, P. -G. Reinhard. 2018-09-06. Excitation spectra of exotic nuclei in a self-consistent phonon-coupling model. https://doi.org/10.1103/physrevc.98.054304

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