Combinatorial level densities by the real-time method
  Levels densities of independent-particle Hamiltonians can be calculated easily by using the real-time representation of the evolution operator together with the fast Fourier transform. We describe the method and implement it with a set of Python programs. Examples are provided for the total and partial levels densities of a heavy deformed nucleus (Dy-164). The partial level densities that may be calculated are the projected ones on neutron number, proton number, azimuthal angular momentum, and parity. 
G.F. Bertsch and L.M. Robledo
nucl-th