Level density and level density parameter in medium heavy nuclei including thermal and quantal fluctuation effects

Abstract

In a realistic application of the SPA + RPA theory for calculation of the nuclear level densities we find that quantal fluctuation corrections (RPA) are important even up to temperature $T=2.0MeV$. This leads to a good agreement between calculated numbers and the available experimental data for ${}^{104}Pd$ and ${}^{114}Sn$, particularly the excitation energy ($E^{\ast }$) dependence. Furthermore, we also argue that $a=S^2/4E^{\ast }$ is the only correct definition of the level density parameter in the present context which is also consistent with the Bethe like level density formula.

Comments: LaTeX file (10 pages), 4 figures (Postscript). (Appearing in Phys. Lett. B)