Dark Matter Deficient Galaxies and Their Member Star Clusters Form Simultaneously during High-velocity Galaxy Collisions in 1.25 pc Resolution Simulations

Rings of Dark Matter in Collisions between Clusters of Galaxies

Several lines of evidence suggest that the galaxy cluster Cl0024+17, an apparently relaxed system, is actually a collision of two clusters, the interaction occurring along our line of sight. Recent lensing observations suggest the presence of a ring-like dark matter structure, which has been interpreted as the result of such a collision. In this paper we present N -body simulations of cluster c...

Shallow dark matter cusps in galaxy clusters

We study the evolution of the stellar and dark matter components in a galaxy cluster of 1015 M from z = 3 to the present epoch using the high-resolution collisionless simulations of Ruszkowski & Springel. At z = 3 the dominant progenitor haloes were populated with spherical model galaxies with and without accounting for adiabatic contraction. We apply a weighting scheme which allows us to chang...

Dark Matter Profile in Clusters of Galaxies

Using X-ray observation we have obtained the deprojected gas density and temperature profiles for a sample of cluster of galaxies. We show that cool-core clusters, which are expected to be the largest relaxed structures in the universe, have central steep mass density profiles, similar to the cold dark matter density profiles resulting from cosmological N-body simulation. We will present detail...

Dark Matter in Clusters of Galaxies

Dark Matter in Dwarf Galaxies: The First Dark Galaxy?

We present new H i observations of the high-velocity cloud (HVC) that we resolved near the Local Group dwarf galaxy LGS 3. The cloud is rotating, with an implied mass that makes it dark matter-dominated no matter what its distance from the Milky Way is. Our new, high-sensitivity Arecibo observations demonstrate that the faint H i features that we previously described as tidal tails are indeed r...