Abstract
The nuclear dipole polarizability is mainly governed by the dynamics of the giant dipole resonance 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.
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This work was supported by the National Research Foundation of South Africa under Grant 93500, the MaNus/MatSci program and the SA-CERN collaboration.
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This article is part of the Topical Collection on Proceedings of the International Conference on Hyperfine Interactions and their Applications (HYPERFINE 2019), Goa, India, 10-15 February 2019
Edited by S. N. Mishra, P. L. Paulose and R. Palit
This work was supported by the National Research Foundation of South Africa, the MaNus/MatSci program and the SA-CERN collaboration.
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Ngwetsheni, C., Orce, J.N. Combined analysis of the low-energy enhancement of the gamma-strength function and the giant dipole resonance. Hyperfine Interact 240, 94 (2019). https://doi.org/10.1007/s10751-019-1618-3
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DOI: https://doi.org/10.1007/s10751-019-1618-3