Galaxy associations within the Coma cluster

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...

Galaxy-cluster associations from gravitational lensing

We investigate the associations between background galaxies and foreground clusters of galaxies due to the effect of gravitational lensing by clusters of galaxies. Similar to the well-known quasar-galaxy ones, these associations depend sensitively on the shape of galaxy number-magnitude or number-flux relation, and both positive and “negative” associations are found to be possible, depending on...

ar X iv : a st ro - p h / 01 02 13 6 v 1 8 F eb 2 00 1 GALAXY ASSOCIATIONS WITHIN THE COMA CLUSTER

The mean redshift of the core of the Coma cluster-cz = 6953 km s −1 and its dispersion σ = 949 km s −1 are obtained by means of the analysis of the substructures of this cluster by using the S-tree method. The existence of three subgroups of galaxies is revealed, one of them is associated with the cD galaxy NGC 4874, the other – with NGC 4889. It is argued that these subgroups are galaxy associ...

Coma Cluster