Fermi-Gas Model Parametrization of Nuclear Level Density.

The authors furnish a new parametrization of the Fermi-Gas model description of nuclear level densities at excitation energies corresponding to the neutron binding energy. The model adopted is the standard Fermi-Gas model with pairing and shell-effect corrections. Particular care has been devoted to the inclusion of shell effects and to their parametrization. The procedure for the evaluation of level density parameters has been applied to a data-base of 217 nuclei covering a mass range 41 ≤ A ≤ 253. A global systematics parametrization has been derived which allows for a derivation of level density parameters for nuclei where experimental information is not available.