SIMBAD references

Within the ESO Key Programme "A search for dark matter in elliptical galaxies", we have performed a detailed study of the large scale stellar kinematics of NGC 1400, 4946, 5812, 6721, 7507, and 7796. Our observations have produced kinematical data down to the 24.1mag/arcsec² in the B band, i.e. in some cases out to 2R_e and beyond. NGC 1400, 4946, and 6721 show significant rotation. The other three galaxies (NGC 5812, 7507, and 7796) can be described by spherical non-rotating equilibrium models. For two of these objects self-consistent stellar dynamical models with constant mass-to-light ratio are found to give good fits to the photometric and kinematical data, although the presence of dark matter is not excluded. In contrast, NGC 7796 shows evidence for the presence of a dark halo. This galaxy also exhibits counterrotation inside 4" and, correspondingly, a central peak in the velocity dispersion profile. On the basis of the small sample of objects studied so far, with radially extended spectroscopic observations, possible trends in the size of dark halos around elliptical galaxies are pointed out.