Unified model of nuclear mass and level density formulas

Fukahori, Tokio  ; Nakamura, Hisashi*

Nuclear ground and excited state properties are described by using parameter systematics on mass and level density formulas. The formulas are based on an analytical expression of the single-particle state density by introducing the shell-paring correction in a new way. Main features are the shell, paring, and deformation effects on the droplet model near the ground state, which are washed out at higher excitation energies. The main aim of this paper is to provide in the analytical framework the improved energy dependent shell, paring, and deformation corrections generalized to the collective enhancement factors, which offer a systematic presentation over a great number of nuclear reactions. The new formulas are shown to be in close agreement with not only the empirical nuclear mass data but also the measured slow neutron resonance spacing and experimental systematics observed in the excitation energy dependent properties.