Constraints on the orbits of multiple nuclei in brightest cluster galaxies

Observations of the velocity and dispersion profiles of the brightest cluster galaxies N6166 and N7720 and their multiple nuclei are presented. The stellar velocity dispersion of the central galaxies demonstrates that the multiple nuclei are not following circular orbits, and that their high relative velocity is not indicative of large mass-to-luminosity ratios in the central galaxy or in the center of the surrounding cluster. The mass-to-luminosity ratios of the central galaxies and the multiple nuclei are indistinguishable from those of other elliptical galaxies.