Systematic studies of photon strength functions with Skyrme- and the derived total dipole resonance properties
Phys. Rev. C 113, 014306 – Published 7 January, 2026
DOI: https://doi.org/10.1103/4z11-s1yc
Abstract
The photon strength function (PSF) of nuclear dipole excitation is greatly important to different applications especially including nuclear astrophysics. However, for the nuclei over the whole nuclear chart, the total electric dipole and magnetic dipole PSF directly derived from large-scale calculation with microscopic theory is not available yet. In this paper, we perform a systematic study on the PSF based on the microscopic Hartree-Fock-Bogoliubov plus quasiparticle random-phase approximation (HFB+QRPA) model used in our previous work of the PSF. In particular, large-scale calculations of the spin-flip strength distributions are performed in the framework of HFB+QRPA under the assumption of spherical symmetry using the BSk27 Skyrme effective interaction. The spin-flip PSFs are obtained by folding the QRPA strength distributions with a Lorentz function that describes the damping of nuclear collective motion empirically. The scissors mode and the low-energy upbend contribution to the PSFs are both added phenomenologically to the spin-flip component. The resulting BSk27+QRPA PSF is shown to be in fairly good agreement with available experimental data. In addition, the comparison between our BSk27+QRPA PSF and other theoretical results indicates that the present approach provides an efficient and reliable alternative to describe the PSF for a large set of nuclei. When consistently considering both our previous and the present BSk27+QRPA PSFs, predictions reasonably reproduce multistep -ray cascade spectra, average radiative widths, and Maxwellian-averaged cross sections. A complete set of and PSFs are determined for nuclei with lying between the proton and the neutron drip lines and used to estimate astrophysical neutron capture rates that are found to be comparable to those obtained with the previous Gogny- predictions based on the D1M interaction.
