Related papers: Luminosity Dependent X-ray AGN Clustering ?

We present the results of a search for galaxy clusters in the first 36 XMM-Newton pointings on the COSMOS field. We reach a depth for a total cluster flux in the 0.5-2 keV band of 3x10-15 ergs cm-2 s-1, having one of the widest XMM-Newton…

X-ray luminosity functions (XLFs) of Active Galactic Nuclei (AGN) trace the growth and evolution of supermassive black hole populations across cosmic time, however, current XLF models are poorly constrained at redshifts of z>6, with a lack…

We use a sample of 151 local non-blazar AGN selected from the INTEGRAL all-sky hard X-ray survey to investigate if the observed declining trend of the fraction of obscured (i.e. showing X-ray absorption) AGN with increasing luminosity is…

Deep extragalactic X-ray surveys, such as the Chandra COSMOS-Legacy field (CCLS), are prone to be biased against active galactic nuclei (AGN) with high column densities due to their lower count rates at a given luminosity. To quantify this…

We present a study of X-ray AGN overdensities in 16 Abell clusters, within the redshift range 0.073<z<0.279, in order to investigate the effect of the hot inter-cluster environment on the triggering of the AGN phenomenon. The X-ray AGN…

Several X-ray properties of active galactic nuclei depend, or appear to depend, on their luminosity. It has long been suggested that alpha o-x, the X-ray ``loudness'' decreases with luminosity. There never has been a satisfactory…

Here we discuss the X-ray properties of clusters of galaxies optically selected in the Red-Sequence Cluster Survey (RCS) observed with the Chandra satellite, at redshifts 0.6 < z < 1.2. We intended to assess the evolutionary stage of…

Only a small fraction of galactic nuclei in the nearby universe are luminous; most of them are currently dim. We investigate the feasibility of constraining the X-ray luminosity in the recent past (up to ~10^6 years ago) of the nucleus of a…

The Chandra Deep Fields (CDFs), being a major thrust among extragalactic X-ray surveys and complemented effectively by multiwavelength observations, have critically contributed to our dramatically improved characterization of the 0.5-8 keV…

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…

In this work, we investigate the dependence of the covering factor (CF) of active galactic nuclei (AGNs) (i) on the mid-infrared (MIR) luminosity and (ii) on the redshift. We constructed 12- and 22-micron luminosity functions (LFs) at 0.006…

Our goal is to find a minimalistic model that describes the luminosity function and large-scale clustering bias of the X-ray-selected AGN in the general framework of the concordance LCDM model. We assume that a simple population-averaged…

We present the clustering properties of hard (2-8 keV) X-ray selected sources detected in a wide field (~2 deg^{2}) shallow [f(2-8 keV)~ 10^{-14} erg cm^{-2} s^{-1}] and contiguous XMM-Newton survey. We perform an angular correlation…

We explore the connections between the infrared and X-ray properties of AGNs. Using the well constrained infrared SEDs of a sample of local (i.e., z < 0.1) sample of X-ray AGNs, we develop new diagnostics that exploit 24um and 70um flux…

We present a detailed and self-consistent modeling of the cosmic X-ray background (XRB) based on the most up-to-date X-ray luminosity functions (XLF) and evolution of Active Galactic Nuclei (AGN). The large body of observational results…

Gravitational lensing by clusters of galaxies affects the cosmic X-ray background (XRB) by altering the observed density and flux distribution of background X-ray sources. At faint detection flux thresholds, the resolved X-ray sources…

Surveys of Active Galactic Nuclei (AGN) in different observational regimes seem to give different answers for the behaviour of the obscured fraction with luminosity. Based on the complex spectra seen in recent studies, we note that partial…

We investigate the clustering and dark halo properties for the narrow-line active galactic nuclei (AGN) in the SDSS, particularly examining the joint dependence on galaxy mass and color. AGN in galaxies with blue colors or massive red…

The first systematic study of the serendipitous X-ray source density around 10 high z (0.24<z<1.2) clusters performed with Chandra is presented. A factor \~2 overdensity has been found in 4 cluster fields. The result is statistically highly…

The spatial clustering of active galactic nuclei (AGNs) is considered to be one of the important diagnostics for the understanding of the underlying processes behind their activities complementary to measurements of the luminosity function…