  Analytical expressions for spectra and wave functions are derived for a Bohr
Hamiltonian, describing the collective motion of deformed nuclei, in which the
mass is allowed to depend on the nuclear deformation. Solutions are obtained
for separable potentials consisting of a Davidson potential in the beta
variable, in the cases of gamma-unstable nuclei, axially symmetric prolate
deformed nuclei, and triaxial nuclei, implementing the usual approximations in
each case. The solution, called the Deformation Dependent Mass (DDM) Davidson
model, is achieved by using techniques of supersymmetric quantum mechanics
(SUSYQM), involving a deformed shape invariance condition. Spectra and B(E2)
transition rates are compared to experimental data. The dependence of the mass
on the deformation, dictated by SUSYQM for the potential used, reduces the rate
of increase of the moment of inertia with deformation, removing a main drawback
of the model.
