Related papers: The Relation Between Activity and Environment in C…
High-redshift galaxy clusters, unlike local counterparts, show diverse star formation activities. However, it is still unclear what keeps some of the high-redshift clusters active in star formation. To address this issue, we performed a…
We study the effect of the extreme environment in Hickson Compact groups (HCGs) on the molecular gas mass, \mhtwo, and the star formation rate (SFR) of galaxies as a function of atomic hydrogen (HI) content and evolutionary phase of the…
We present early results of the Herschel PACS (70 and 160 \micron{}) and SPIRE (250, 350, and 500 \micron{}) survey of 313 low redshift ($\rm{z} < 0.05$), ultra-hard X-ray (14--195 keV) selected AGN from the 58 month Swift/BAT catalog.…
In galaxy clusters, efficiently accreting active galactic nuclei (AGN) are preferentially located in the infall regions of the cluster projected phase-space, and are rarely found in the cluster core. This has been attributed to both an…
[Abridged] We present an analysis of optical spectroscopically-identified AGN to M*+1 in a sample of 6 self-similar SDSS galaxy clusters at z=0.07. These clusters are specifically selected to lack significant substructure at bright limits…
Observations show that galaxies in galaxy clusters are strongly influenced by their environment. There is growing evidence that some galaxies in groups show similar properties to galaxies in clusters, such as redder colours and gas…
(Abridged) The Spitzer Survey for Stellar Structure in Galaxies (S4G) and its more recently approved extension will lead to a set of 3.6 and 4.5 micron images for 2829 galaxies, which can be used to study many different aspects of the…
The correlation between active galactic nuclei (AGN) and environment provides important clues to AGN fueling and the relationship of black hole growth to galaxy evolution. In this paper, we analyze the fraction of galaxies in clusters…
We perform a comparison of the properties of galaxies in compact groups, loose groups and in the field to deepen our understanding of the physical mechanisms acting upon galaxy evolution in different environments. We select samples of…
We present the first systematic 1.4 GHz Very Large Array radio continuum survey of fossil galaxy group candidates. These are virialized systems believed to have assembled over a gigayear in the past through the merging of galaxy group…
We present the observed fraction of galaxies with an Active Galactic Nucleus (AGN) as a function of environment in the Early Data Release of the Sloan Digital Sky Survey (SDSS). Using 4921 galaxies between 0.05 <= z <= 0.095, and brighter…
We obtained new Fabry-Perot data cubes and derived velocity fields, monochromatic and velocity dispersion maps for 28 galaxies in the Hickson compact groups 37, 40, 47, 49, 54, 56, 68, 79 and 93. We find that one third of the non-barred…
We present CO(1-0) maps of 12 warm H$_2$-selected Hickson Compact Groups (HCGs), covering 14 individually imaged warm H$_2$ bright galaxies, with CARMA. We found a variety of molecular gas distributions within the HCGs, including regularly…
Using a simple two-color selection based on $g$-, $z$-, and $K$-band photometry, we pick out 1609 star-forming galaxies (sgzKs) and 422 passively evolving galaxies (pgzKs) at z\sim2$ from a $K$-band-selected sample ($K_{\rm AB} < 22.0$) in…
We present an analysis of the X-ray Active Galactic Nucleus (AGN) population in a sample of seven massive galaxy clusters in the redshift range $0.35<z<0.45$. We utilize high-quality Chandra X-ray imaging to robustly identify AGN and…
We aim to study the effect of environment on the presence and fuelling of Active Galactic Nuclei (AGN) in massive galaxy clusters. We explore the use of different AGN detection techniques with the goal of selecting AGN across a broad range…
We present the first results from the COLA (Compact Objects in Low-power AGN) project which aims to determine the relationship between one facet of AGN activity, the compact radio core, with star formation in the circumnuclear region of the…
We use catalogues of superclusters of galaxies from the 2dF Galaxy Redshift Survey to study the properties of galaxies in superclusters. We compare the properties of galaxies in high and low density regions of rich superclusters, in poor…
Compact groups of galaxies have posed a number of challenging questions. Intensive observational and theoretical studies are now providing answers to many of these, and at the same time, are revealing unexpected new clues about the nature…
Using the TNG100 cosmological simulation, we study the formation and evolution of compact groups of galaxies. Over a redshift range of $0 \lesssim z \lesssim 0.2$, we identify these compact groups as FoF galaxy groups with high mean surface…