In this paper we present deep VLT multi wavelength imaging observations of the field around the radio galaxy PKS 1138−262 aimed at detecting and studying a (potential) proto-cluster centered at this radio source. PKS 1138−262 is a massive galaxy at z = 2.16, located in a dense environment as indicated by optical, X-ray and radio observations. We had already found an over-density of Lyα emitting...

MeerKAT's large number of antennas, spanning 8 km with a densely packed 1 core, create powerful instrument for wide-area surveys, high sensitivity over wide range angular scales. The MeerKAT Galaxy Cluster Legacy Survey (MGCLS) is programme long-track L-band (900-1670 MHz) observations 115 galaxy clusters, observed $\sim$6-10 hours each in full polarisation. first legacy product data release (D...

We present the discovery of a 70 kpc X-ray tail behind the small late-type galaxy ESO 137-001 in the nearby, hot (T=6.5 keV) merging cluster A3627, from both Chandra and XMM-Newton observations. The tail has a length-to-width ratio of ∼ 10. It is luminous (L 0.5−2keV ∼ 10 41 ergs s −1), with a temperature of ∼ 0.7 keV and an X-ray M gas of ∼ 10 9 M ⊙ (∼ 10% of the galaxy's stellar mass). We int...

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 ...

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 ...

We investigate the importance of projection effects in the identification of galaxy clusters in 2D galaxy maps and their effect on the estimation of cluster velocity dispersions. From large N-body simulations of a standard cold dark matter universe, we construct volume-limited galaxy catalogues that have similar low-order clustering properties to those of the observed galaxy distribution. We th...

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 ...