Invited review presented at IAU Symposium 317: The General Assembly of Galaxy Halos, 2015.

For a PDF version of the article, click here.


J. Christopher Mihos

Department of Astronomy, Case Western Reserve University

Abstract: The largest stellar halos in the universe are found in massive galaxy clusters, where interactions and mergers of galaxies, along with the cluster tidal field, all act to strip stars from their host galaxies and feed the diffuse intracluster light (ICL) and extended halos of brightest cluster galaxies (BCGs). Studies of the nearby Virgo Cluster reveal a variety of accretion signatures imprinted in the morphology and stellar populations of its ICL. While simulations suggest the ICL should grow with time, attempts to track this evolution across clusters spanning a range of mass and redshift have proved difficult due to a variety of observational and definitional issues. Meanwhile, studies of nearby galaxy groups reveal the earliest stages of ICL formation: the extremely diffuse tidal streams formed during interactions in the group environment.

Keywords. galaxies: clusters, galaxies: halos, galaxies: evolution

Table of Contents