Related papers: Distant galaxy clusters in the COSMOS field found …
High-redshift protoclusters are crucial for understanding the formation of galaxy clusters and the evolution of galaxies in dense environments. The James Webb Space Telescope (JWST), with its unprecedented near-infrared sensitivity, enables…
Identification of high redshift clusters is important for studies of cosmology and cluster evolution. Using photometric redshifts of galaxies, we identify 631 clusters from the Canada-France-Hawaii Telescope (CFHT) Wide field, 202 clusters…
We have collected optical follow-up observations from the ground and the Hubble Space Telescope (HST) for 13.74 square ' of archival images taken with the Near Infrared Camera and Multi Object Spectrograph (NICMOS). We use two criteria to…
We present a deep X-ray selected sample of galaxy clusters which has been created from a serendipitous search in ROSAT-PSPC deep pointed observations at high galactic latitude. This survey, hereafter known as the ROSAT Deep Cluster Survey…
In this paper, we present the tools used to search for galaxy clusters in the Kilo Degree Survey (KiDS), and our first results. The cluster detection is based on an implementation of the optimal filtering technique that enables us to…
We summarize our work on structures in different stages of aggregation, and spanning a wide range in redshift. We emphasize our work on high resdhift clusters. This comprises the analysis of ~7 square degrees using deep images with several…
We present measurements of the clustering properties of galaxies in the field of redshift range $0.5 \lesssim z \lesssim 1.5$ Ultra Steep Spectrum (USS) radio sources selected from Sydney University Molonglo Sky Survey and NRAO VLA Sky…
Dense environments have an impact on the star formation rate of galaxies. As stars form from molecular gas, looking at the cold molecular gas content of a galaxy gives useful insights on its efficiency in forming stars. However, most…
I review recent observational progress in the search for and study of distant galaxy clusters in the X-ray band, with particular emphasis on the evolution of the abundance of X-ray clusters out to z~1. Several on-going deep X-ray surveys…
We report the discovery of a probable large scale structure composed of many galaxy clumps around the known twin clusters at z=1.26 and z=1.27 in the Lynx region. Our analysis is based on deep, panoramic, and multi-colour imaging…
The abundance of elliptical, S0 and spiral galaxies in clusters is presented as a function of redshift comparing the results of the HST distant cluster studies with new data at z~0.2 and with the standard local comparison samples. This…
Recent studies have shown that distant red galaxies (DRGs), which dominate the high-mass end of the galaxy population at z~2.5, are more strongly clustered than the population of blue star-forming galaxies at similar redshifts. However…
We present some initial results from the TexOx (Texas-Oxford) Cluster (TOC) survey - a new method of selecting distant galaxy clusters. The cosmic evolution of the radio source population suggests that some massive clusters at high redshift…
An analysis of the cluster environments around distant radio galaxies is presented, in particular the results from new NTT deep optical-IR imaging of the fields of radio sources at z ~ 1.6. A net overdensity of K-band galaxies is found,…
A field of 1.013 ster in the ROSAT all-sky survey (RASS), centered on the south galactic pole (SGP), has been searched in a systematic, objective manner for clusters of galaxies. The procedure relied on a correlation of the X-ray positions…
We select galaxy cluster candidates from the high-redshift (BEST_Z > 0.9) end of the first SRG/eROSITA All-Sky Survey (eRASS1) galaxy cluster catalogue, for which we obtain moderately deep J-band imaging data with the OMEGA2000 camera at…
The wide-area imaging surveys with the {\it Herschel} Space Observatory at sub-mm wavelengths have now resulted in catalogs of order one hundred thousand dusty, star-burst galaxies. We make a statistical estimate of $N(z)$ using a…
Using accurate positions from very deep radio observations to guide multi-object Keck spectroscopy, we have determined a substantially complete redshift distribution for very luminous, distant submillimeter(submm)-selected galaxies (SMGs).…
A comparison of the correlation lengths of red galaxies with blue can provide a new cosmic ruler. Using 269,000 galaxies from the SDSS DR6 survey, I show that the 3D correlation length averaged over many clusters remains very nearly…
This paper presents 52 X-ray bright galaxy clusters selected within the 11 deg$^2$ XMM-LSS survey. 51 of them have spectroscopic redshifts ($0.05<z<1.06$), one is identified at $z_{\rm phot}=1.9$, and all together make the high-purity…