S. Sridhar et J. Touma, 3-DIMENSIONAL, AXISYMMETRICAL CUSPS WITHOUT CHAOS, Monthly Notices of the Royal Astronomical Society, 292(3), 1997, pp. 657-661
We construct three-dimensional axisymmetric, cuspy density distributio
ns, whose potentials are of Stackel form in parabolic coordinates. As
in a recent paper by Sridhar BL Touma, a black hole of arbitrary mass
may be added at the centre, without destroying the Stackel form of the
potentials. The construction uses a classic method, originally owing
to Kuzmin, which is extended to parabolic coordinates here. The models
are highly oblate, and the cusps are 'weak', with the density, rho pr
oportional to 1/r(k), where 0<k<1.