Statistical properties and stability of hot nuclei in a semiclassical relativistic approach

Within the finite-temperature relativistic mean field theory models (linear and nonlinear) and using the local density approximation, the statistical properties and stability of hot nuclei are investigated. It is found that the nonlinear model presents higher thermal response than the linear model. The critical temperature is found to be about 9 MeV for the linear model and about 8 MeV for the nonlinear one. The value of the energy level density parameter obtained by the nonlinear model is found to be of the order of 0.11 ${\mathrm{MeV}}^{\mathrm{-}1}$, in good agreement with the empirical value ≃0.12 ${\mathrm{MeV}}^{\mathrm{-}1}$. The linear model gives smaller values. The nonrelativistic limit of the linear model indicates that the relativistic treatment increases the excitation.