Combined analysis of the low-energy enhancement of the gamma-strength function and the giant dipole resonance

Abstract

onance and has been investigated along with the effects of the low-energy enhancement of the photon strength function for nuclides in medium-and heavy-mass nuclei. Cubic-spline interpolations to both data sets show a significant reduction of the nuclear dipole polarizability for semi-magic and doubly magic nuclei, with magic numbers N = 28, 50, 82 and 126, which supports shell effects at high-excitation energies from the quasi-continuum to the giant dipole resonance. This work expands on the data analysis of our recent publication in Ngwetsheni and Orce (Phys. Lett. B 792, 335, 2019), which reveals a new spectroscopic probe to search for "old" and "new" magic numbers at high-excitation energies. New results presented in this work suggest an even higher sensitivity of the nuclear polarizability to shell effects when extrapolating the low-energy enhancement at lower gamma-ray energies.

Electric dipole polarizability of low-lying excited states in atomic nuclei

“…In this work, we further explore how the E1 polarizability evolves from the ground state to the first excitation of selected p-and sd-shell nuclides. Where possible, we perform 1ÿω SM calculations, compare with available data and explore deviations from the hydrodynamic model [59,60,[63][64][65]. Similar SM calculations of the E1 polarizability for ground states have already been published in [52].…”