相关论文: Luminous X-ray AGN in Clusters of Galaxies
We present a study of the overdensity of X-ray selected AGN in 33 galaxy clusters in the XMM-LSS field, up to redhift z=1.05. Previous studies have shown that the presence of X-ray selected AGN in rich galaxy clusters is suppressed. In the…
The analysis of the cluster environment is a valuable instrument to investigate the origin of AGN and star-forming galaxies gas fuelling and trigger mechanisms. To this purpose, we present a detailed analysis of the point-like X-ray sources…
Observational constraints on the average radial distribution profile of AGN in distant galaxy clusters can provide important clues on the triggering mechanisms of AGN activity in dense environments and are essential for a completeness…
Two nearby clusters of galaxies: A194 (z=0.018) and A1060 (z=0.0114) have been analyzed for their X-ray point source properties with XMM-Newton EPIC-PN data. A multi-band source detection technique was applied to both of the clusters,…
We investigate the prevalence of AGN in the high-redshift protocluster $\rm{Cl}\,0218.3$-$0510$ at $z=1.62$. Using imaging from the Chandra X-ray Telescope, we find a large overdensity of AGN in the protocluster; a factor of $23\pm9$ times…
We study the spatial distribution of a 95% complete sample of 508 X-ray point sources (XPS) detected in the 0.5-2.0 keV band in Chandra ACIS-I observations of 51 massive galaxy clusters found in the MACS survey. Covering the redshift range…
In this work, we studied ten nearby ($z$$ \leq$0.038) galaxy clusters to understand possible interactions between hot plasma and member galaxies. A multi-band source detection was applied to detect point-like structures within the…
We present the results of a new analysis of the X-ray selected Active Galactic Nuclei (AGN) population in the vicinity of 135 of the most massive galaxy clusters in the redshift range of 0.2 < z < 0.9 observed with Chandra. With a sample of…
As an evolutionary phase of galaxies, active galactic nuclei (AGN) over a large range of redshift have been utilized for understanding cosmic evolution. In particular, the population and evolution of AGNs have been investigated through the…
As part of a program to study the evolution of active galactic nuclei (AGN) in clusters of galaxies, we present our results for Abell 2104. A deep Chandra observation of this massive, z = 0.154 cluster reveals a significant X-ray point…
The environments of a complete subsample of 6 of the most powerful radio-loud AGN at redshifts z~1.6 are investigated, using deep RJK imaging to depths of R~26, J~22.4 and K~20.6. An excess of galaxy counts in the K-band is seen across…
We have completed a spectroscopic survey of X-ray point sources in eight low-redshift clusters of galaxies (0.05<z<0.31) and have identified 40 cluster members with broad-band (0.3-8 keV) X-ray luminosities between L_X = 8x10^{40} and…
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 an analysis of the X-ray point source populations in 182 Chandra images of galaxy clusters at z>0.1 with exposure time >10 ksec, as well as 44 non-cluster fields. Analysis of the number and flux of these sources, using a detailed…
Most galaxies in clusters have supermassive black holes at their center, and a fraction of those supermassive black holes show strong activity. These active galactic nuclei(AGNs) are an important probe of environmental dependence of galaxy…
We explore the role of the group environment in the evolution of AGN at the redshift interval 0.7<z<1.4, by combining deep Chandra observations with extensive optical spectroscopy from the All-wavelength Extended Groth strip International…
To better understand the mechanism or mechanisms that lead to AGN activity today, we measure the X-ray AGN fraction in a new sample of nearby clusters and examine how it varies with galaxy properties, projected cluster-centric radius, and…
The first systematic study of the serendipitous X-ray source density around 10 high z (0.24<z<1.2) clusters has been performed with Chandra. A factor ~2 overdensity has been found in 4 cluster fields, increasing to 11 the number of known…
This work is part of a series of studies focusing on the environment and the properties of the X-ray selected active galactic nuclei (AGN) population from the XXL survey. The present survey, given its large area, continuity, extensive…