2000AJ....119..153S

Accurate and radially extended stellar kinematic data reaching R=97'' from the center are presented for the cD galaxy of Fornax NGC 1399. The stellar rotation is small (≤30 km.s^–1); the stellar velocity dispersion remains constant at 250-270 km.s^–1. The deviations from Gaussian line-of-sight velocity distributions are small, at the percent level. We construct dynamical models of the galaxy, deprojecting its nearly round (E0-E1) surface brightness distribution and determining the spherical distribution function that best fits (at the 4% level) the kinematic data on a grid of parameterized potentials. We find that the stellar orbital structure is moderately radial, with β=0.3±0.1 for R≤60'', similar to results found for some normal giant elliptical galaxies. The gravitational potential is dominated by the luminous component out to the last data point, with a mass-to-light ratio M/L_B=10(M/L)_☉, although the presence of a central black hole of M~5x10⁸ M_☉ is compatible with the data in the inner 5". The influence of the dark component is marginally detected starting from R~60''. Using the radial velocities of the globular clusters and planetary nebulae of the galaxy, we constrain the potential more strongly, ruling out the self-consistent case and finding that the best-fit solution agrees with X-ray determinations. The resulting total mass and mass-to-light ratio are M=1.2-2.5x10¹² M_☉ and M/L_B=2-48(M/L)_☉ inside R=417'' or 35 kpc for D=17.6 Mpc.