Benedetta VULCANI
(KAVLI IPMU)
Central galaxies in massive halos live in unique environments.Studies focused on brightest cluster galaxies found that they are often peculiar in terms of size,dynamical structure.The reasons for these differences remain untested.Is there a critical halo mass and redshift at which the central galaxy differentiates from its satellites or from other massive galaxies in the field?I will present an analysis of the fundamental plane of a spectroscopic sample of~60BCGs in COSMOS X-ray selected groups(0.2<z<0.8),comparing their properties to a control sample.I find evidence for larger sizes,but similar dynamical scaling relations,suggesting a relatively mild merger history that may be at odds with the rapid recent assembly expected for their host halos.