Calculation of nuclear level density using the microscopic statistical model with Hartree-Fock-Bogoliubov theory

Furutachi, Naoya; Minato, Futoshi   ; Iwamoto, Osamu  

The nuclear level density is essential for nuclear reaction calculations using the statistical model and pre-equilibrium models. Phenomenological Fermi gas models have been used widely for calculations of the nuclear level density, however, reliability of them depend on the parameter adjustment to reproduce the experimental informations of the s-wave neutron resonance spacing D0, and therefore, calculations using more microscopic models are desirable for unstable nuclei that have no available experimental information. The microscopic statistical models and combinatorial models based on Hartree-Fock theory are models that can reproduce the experimental D0 with precisions comparable to the phenomenological models. However, these calculations are strongly dependent on the strength of the pairing interaction, and its uncertainty affect to the precision of the calculations. Therefore, in this work, we improved the treatment of the pairing interaction in the nuclear structure calculation, and analyzed how the pairing interaction affect to the precision of the nuclear level density calculation.