2 INTEGRAL DYNAMICAL MODELS FOR DISKS WITH ALMOST CIRCULAR ORBITS

We present global dynamical models for disk systems. The structure in phase-space is examined by means of axisymmetric two integral distribu tion functions where stars travel on nearly circular orbits. Those mod els indicate that the maximum phase-space density does not necessarily occur in the center, but can be as much as 100 times larger than the central value. This observation may be important if ellipticals are th e merger remnants of such disk systems. Furthermore, the ratio of disp ersions sigma2psi/sigma2omega is not always a good indicator for B/B-A . The particular method of construction we used, suggests that the det ermination of the distribution function from the mass density is sensi tive to the detailed structure of the latter, but not as unstable as m ethods that do not incorporate the positivity of the distribution func tion.