DARK-MATTER IN ELLIPTIC GALAXIES

We present measurements of the shape of the stellar line-of-sight velo city distribution out to two effective radii along the major axes of t he four elliptical galaxies NGC 2434, 2663, 3706, and 5018. The veloci ty dispersion profiles are flat or decline gently with radius. We comp are the data to the predictions of f = f(E, L(z)) axisymmetric models with and without dark matter. Strong tangential anisotropy is ruled ou t at large radii. We conclude from our measurements that massive dark halos must be present in three of the four galaxies, while for the fou rth galaxy (NGC 2663) the case is inconclusive.