Galaxy Orientations in the Coma Cluster

DETECTION OF NON-RANDOM GALAXY ORIENTATIONS IN X-ray SUBCLUSTERS OF THE COMA CLUSTER

This study on the Coma cluster suggests that there are deviations from a completely random galaxy orientation on small scales. Since we found a significant coincidence of hot-gas features identified in the latest X-ray observations of Coma with these local anisotropies, they may indicate regions of recent mutual interaction of member galaxies within subclusters which are currently falling in on...

Galaxy Aggregates in the Coma Cluster

We present evidence for a new morphologically defined form of small-scale substructure in the Coma Cluster, which we call galaxy aggregates. These aggregates are dominated by a central galaxy, which is on average three magnitudes brighter than the smaller aggregate members, nearly all of which lie to one side of the central galaxy. We have found three such galaxy aggregates dominated by the S0 ...

The Mass Profile of the Coma Galaxy Cluster

We use a new redshift survey complete to mR ≃ 15.4 within 4.25 o from the center of the Coma cluster to measure the mass profile of the cluster to r ∼ 5.5h Mpc. We extend the profile to r ∼ 10h Mpc with a further sample complete to mR = 15.4 in 42% of the area within a 10 radius and to mZw = 15.5 in the remaining area. Galaxies within this region are falling onto the cluster on moderately radia...

Coma Cluster

Dark matter distribution in the Coma cluster from galaxy kinematics: breaking the mass-anisotropy degeneracy

We study velocity moments of elliptical galaxies in the Coma cluster using Jeans equations. The dark matter distribution in the cluster is modelled by a generalised formula based upon the results of cosmological N -body simulations. Its inner slope (cuspy or flat), concentration, and mass within the virial radius are kept as free parameters, as well as the velocity anisotropy, assumed independe...