Static path approximation in deformed nuclei

The static path approximation to the partition function of a nucleus is studied for Hamiltonians with quadrupole-quadrupole interactions. The static path approximation yields a higher level density than the finite-temperature Hartree theory due to a better treatment of the deformation degrees of freedom. The level density is further increased when the nucleus has a static deformation. Comparing with the exact partition function of the Elliott SU(3) model, the static path approximation is found to be remarkably accurate and far superior to finite-temperature Hartree theory.