The standard method of modeling axisymmetric stellar systems begins from the assumption that mass follows light. The gravitational potential is then derived from the luminosity distribution, and the unique two-integral distribution function f(E,L2z) that generates the stellar density in this potential is found. It is shown that the gravitational potential can instead be generated directly from the velocity data in a two-integral galaxy, thus allowing one to drop the assumption that mass follows light. The two-dimensional rotational velocity field can also be recovered in a model-independent way. Regularized algorithms for carrying out the inversions are presented and tested by application to pseudo-data from a family of oblate models.
The Astronomical Journal
- Pub Date:
- September 1996
- STARS: LUMINOSITY FUNCTION;
- STARS: MASS FUNCTION;
- GALAXIES: KINEMATICS AND DYNAMICS;
- 23 LATEX pages, 5 Postscript figures, uses AASTEX, epsf.sty. To appear in The Astronomical Journal, Vol. 112, September 1996