The Origin and Properties of Intracluster Stars in a Rich Cluster

This is a z=0 image of a high resolution SPH simulation of a Coma-like galaxy cluster formed in a cosmological context. This simulation was done using Gasoline, as part of the University of Washington's N-Body shop, and run at the Arctic Region Supercomputing Center. We used the results of this simulation to study The Origin and Properties of Intracluster Stars in a Rich Cluster in unprecedented detail.


Clicky for a movie showing the evolution of the cluster from z = 1.25 to z = 0 (it may take a minute to download). The two most luminous halos you see infall are roughly the mass of Fornax and Virgo, respectively. This movie was made using software written by James Wadsley.


This image is a velocity-density map of the stars in a Coma cluster formed in an SPH simulation in a cosmological context. The contours represent mass density and the colors represent velocity, where stars in blue pixels are on average moving towards the observed and stars in red pixels are on average moving away from the observer. Each pixel represents a 30'x30' field at a distance of 1.5 Mpc (the distance of the Virgo Cluster) and the x and y axes show position in kpc. In this projection, the stellar density (i.e. luminosity) contours display no clear evidence of tidal streamers. However, the velocity map underscores a recent tidal stripping event: the stream of blue pixels extending off of the small halo at [-6600,-800] shows that those stars are at nearly the same radial velocity as those bound to the halo, suggesting that they are dynamically connected to the halo.