Simultaneous microscopic description of nuclear level density and radiative strength function

TL;DR

This paper presents a microscopic approach that simultaneously describes nuclear level density and radiative strength function, emphasizing the importance of exact thermal pairing and challenging the Brink-Axel hypothesis.

Contribution

It introduces a model that accounts for thermal effects and giant resonances, providing improved agreement with experimental data for Yb isotopes.

Findings

Good agreement with experimental data for Yb isotopes

Highlights the importance of exact thermal pairing

Challenges the Brink-Axel hypothesis in RSF description

Abstract

Nuclear level density (NLD) and radiative strength function (RSF) are described simultaneously within a microscopic approach, which takes into account the thermal effects of the exact pairing as well as the giant resonances within the phonon-damping model. The good agreement between the results of calculations and experimental data extracted by the Oslo group for $^{170, 171, 172}$Yb isotopes shows the importance of exact thermal pairing in the description of NLD at low and intermediate excitation energies and invalidates the assumption based on the Brink-Axel hypothesis in the description of the RSF.