The Survival of The Core Fundamental Plane Against Galactic Mergers

Abstract

We have developed an effective simulation method and applied it to the problem of the accretion of very dense secondary companions by tenuous primaries. We have studied the accretion of objects of varying luminosity ratios, with sizes and densities drawn from the core Fundamental Plane for elliptical galaxies under the assumption that the mass distribution in the central parts of the galaxies follows the light. The results indicate that in mergers with mass ratios greater than 10, the smaller object is only stripped down to the highest density encountered in the primary during the accretion process. Thus, the form of the core Fundamental Plane suggests that the mass distribution in these galaxy centers is different than the light distribution, or that mergers on the core Fundamental Plane require more than the dynamics of visible stars.