Related papers: Unveiling the distribution of absorption in the AG…
We have used very deep XMM-Newton observations of the Chandra Deep Field-South to examine the spectral properties of the faint active galactic nucleus (AGN) population. Crucially, redshift measurements are available for 84% (259/309) of the…
We present an analysis of the X-ray properties of sources detected in the 13H XMM-Newton deep (200ks) field. In order to constrain the absorbed AGN population, we use extensive Monte Carlo simulations to directly compare the X-ray colours…
(ABRIDGED) We investigate here the XLF of absorbed (Nh between 4E21 and E24 cm-2) and unabsorbed (Nh < 4E21 cm-2) AGN, the fraction of absorbed AGN as a function of Lx (and z), the intrinsic Nh distribution of the AGN population, and the…
We present selected results on the X-ray spectroscopy of distant, obscured AGN as obtained with the ultra-deep (~3 Ms) XMM-Newton survey in the Chandra Deep Field South (CDF-S). One of the primary goals of the project is to characterize the…
We combine bright XMM data with the Chandra Deep Field South observations in order to explore the behavior of the intrinsic AGN absorption, as a function of redshift and luminosity.Our sample consists of 359 sources selected in the hard 2-8…
We have measured the X-ray spectral properties of a complete flux-limited sample of bright AGNs from HEAO-1 all-sky catalogs to investigate their statistics and provide greater constraints on the bright-end of the hard X-ray luminosity…
We present the most up-to-date X-ray luminosity function (XLF) and absorption function of Active Galactic Nuclei (AGNs) over the redshift range from 0 to 5, utilizing the largest, highly complete sample ever available obtained from surveys…
The XLF of AGN offers a robust tool to study the evolution and the growth of SMBHs over cosmic time. Owing to the limited area probed by X-ray surveys, optical surveys are routinely used to probe the accretion in the high redshift Universe…
We present the X-ray luminosity function of AGN in three energy bands (Soft: 0.5-2 keV, Hard: 2-10 keV and Ultrahard: 4.5-7.5 keV). We have used the XMS survey along with other highly complete flux-limited deeper and shallower surveys for a…
Intrinsic absorption is a fundamental physical property to understand the evolution of active galactic nuclei (AGN). Here a sample of 1290 AGN, selected in the 2-10 keV band from different flux-limited surveys with very high optical…
Modern cosmological simulations rely heavily on feedback from active galactic nuclei (AGN) in order to stave off overcooling in massive galaxies and galaxy groups and clusters. An important independent test is whether or not the simulations…
We present new measurements of the evolution of the X-ray luminosity functions (XLFs) of unabsorbed and absorbed Active Galactic Nuclei (AGNs) out to z~5. We construct samples containing 2957 sources detected at hard (2-7 keV) X-ray…
Our goal is to probe the populations of obscured and unobscured AGN investigating their optical-IR and X-ray properties as a function of X-ray flux, luminosity and redshift within a hard X-ray selected sample of 136 X-ray sources in the XMM…
We present broadband properties of sources in the Chandra Deep Field-North with spectroscopic redshifts. The high luminosity and redshift bins are dominated by typical quasars. The intermediate redshift (z = 0.7-1.5) and luminosity ranges…
We present the first direct measurements of the rest-frame 10-40 keV X-ray luminosity function (XLF) of Active Galactic Nuclei (AGNs) based on a sample of 94 sources at 0.1 < z <3, selected at 8-24 keV energies from sources in the NuSTAR…
We present the first results of the spectroscopy of distant, obscured AGN as obtained with the ultra-deep (~3.3 Ms) XMM-Newton survey in the Chandra Deep Field South (CDFS). One of the primary goals of the project is to characterize the…
We present here a detailed X-ray spectral analysis of the AGN belonging to the XMM-Newton bright survey (XBS) that comprises more than 300 AGN up to redshift ~ 2.4. We performed an X-ray analysis following two different approaches: by…
We review some of the main physical and statistical properties of the X-ray absorber in AGNs. In particular, we review the distribution of the absorbing column density inferred from X-ray observations of various AGN samples. We discuss the…
We present a detailed spectral analysis of point-like X-ray sources in the XMM-COSMOS field. Our sample of 135 sources only includes those that have more than 100 net counts in the 0.3-10 keV energy band and have been identified through…
It is well accepted that unabsorbed as well as absorbed AGN are needed to explain the nature and the shape of the Cosmic X-ray background, even if the fraction of highly absorbed objects (dubbed Compton-thick sources) substantially still…