Landau theory of nuclear level density and its application in description of nuclear level density in the region of discrete and s-wave neutron resonance energies

TL;DR

This paper tests the Landau model's effectiveness in describing nuclear level densities across various nuclei and energy ranges, demonstrating its superiority over traditional models in matching experimental data.

Contribution

It is the first to evaluate the Landau expression's accuracy for nuclear level densities at discrete and s-wave neutron resonance energies across different nuclei.

Findings

Landau model outperforms back-shifted Fermi-gas and constant temperature models.

Landau expression provides better fit to experimental data in discrete energy range.

Results valid for nuclei near neutron binding energy.

Abstract

In this work, the reliability of the Landau expression for the nuclear level density calculations is tested, for the first-time, to describe nuclear level densities of some light, intermediate mass and heavy nuclei at excitations corresponding to discrete and s-wave neutron resonance energies. The chi-2 minimizing method is used in treatment of the experimental data for the two suggested energy range of discrete energies given by Nuclear Data Sheet [1] and by the systematic for nuclear level density parametrization in [2]. Our comparison with the related data in the discrete energy range has shown that the results obtained by the Landau expression are better than those of back-shifted Fermi-gas model and constant temperature approximation. This result is also valid for some nuclei of interest when the s-wave neutron resonance level density is included to check theoretical prescriptions in the energy range from initial bound states to unbound states near the neutron binding energy.