Related papers: Unveiling obscured accretion
We investigated the properties of 94 [NeV]3426AA-selected type 2 AGN in COSMOS at z=0.6-1.2, performing optical-to-far-infrared spectral energy distribution fitting. In addition, we analyze the X-ray spectra of the X-ray-detected sources to…
We investigate the population of high-redshift ($3\leq z < 6$) AGN selected in the two deepest X-ray surveys, the 7 Ms \textit{Chandra} Deep Field-South and 2 Ms \textit{Chandra} Deep Field-North. Their outstanding sensitivity and spectral…
We review recent evidence for a clear association between accretion onto supermassive black holes and star formation up to z~1 in the zCOSMOS survey. Star formation rates (SFRs) are determined from the [OII] emission-line strength and a…
Approximately 3-17 percent of Active Galactic Nuclei (AGN) without detected rest-frame UV/optical broad emission lines (type-2 AGN) do not show absorption in X-rays. The physical origin behind the apparently discordant optical/X-ray…
We discuss the relationship between rest-frame color and optical luminosity for X-ray sources in the range 0.6<z<1.4 selected from the Chandra survey of the Extended Groth Strip (EGS). These objects are almost exclusively active galactic…
We use deep Chandra X-ray imaging to measure the distribution of specific black hole accretion rates ($L_X$ relative to the stellar mass of the galaxy) and thus trace AGN activity within star-forming and quiescent galaxies, as a function of…
We present a detailed comparison between the 2-10 keV hard X-ray and infrared (IR) luminosity function (LF) of active galactic nuclei (AGN). The composite X-ray to IR spectral energy distributions (SEDs) of AGN used for connecting the hard…
Most Active Galactic Nuclei (AGN) are `obscured', i.e. the nucleus is hiding behind a screen of absorbing material. The advantage of having the nucleus obscured is to make easier the observations of those emission components which originate…
We present a first attempt to derive the cosmological evolution of the kinetic luminosity function of AGN based on the joint evolution of the flat spectrum radio and hard X-ray selected AGN luminosity functions. An empirical correlation…
We build a simple physical model to study the high-redshift active galactic Nucleus (AGN) evolution within the co-evolution framework of central black holes (BHs) and their host galaxies. The correlation between the circular velocity of a…
The optical spectroscopic classification of active galactic nuclei (AGN) into type 1 and type 2 can be understood in the frame of the AGN unification models. However, it remains unclear which physical properties are driving the…
Deep X-ray surveys have shown that the cosmic X-ray background (XRB) is largely due to the accretion onto supermassive black holes, integrated over the cosmic time. These surveys have resolved more than 80% of the 0.1-10 keV X-ray…
Current X-ray surveys have proved to be essential tools in order to identify and study AGNs across cosmic time. However, there is evidence that the most heavily obscured AGNs are largely missing even in the deepest surveys. The search for…
We investigate the Eddington ratio distribution of X-ray selected broad-line active galactic nuclei (AGN) in the redshift range 1.0<z<2.2, where the number density of AGNs peaks. Combining the optical and Subaru/FMOS near-infrared…
We report on an optical (SDSS) and X-ray (XMM) study of an optically selected sample of four dual AGN systems at projected separations of 30--60~kpc. All sources are detected in the X-ray band (0.3-10 keV); seven objects are optically…
We present a new modeling of the X-ray luminosity function (XLF) of Active Galactic Nuclei (AGN) out to z$\sim$3, dissecting the contribution of main-sequence (MS) and starburst (SB) galaxies. For each galaxy population, we convolved the…
We present the hard-band ($2-10\,\mathrm{keV}$) X-ray luminosity function (HXLF) of $0.5-2\,\mathrm{keV}$ band selected AGN at high redshift. We have assembled a sample of 141 AGN at $3<z\lesssim5$ from X-ray surveys of different size and…
The wide-area XMM-XXL X-ray survey is used to explore the fraction of obscured AGN at high accretion luminosities, $L_X (\rm 2-10 \, keV) > 10^{44} \, erg \,s ^{-1}$, and out to redshift $z\approx1.5$. The sample covers an area of about…
The coevolution between supermassive black holes (SMBHs) and their host galaxies has been proposed for more than a decade, albeit with little direct evidence about black hole accretion activities regulating galaxy star formation at $z>1$.…
In order to relate the observed evolution of the galaxy stellar mass function and the luminosity function of active galactic nuclei (AGN), we explore a co-evolution scenario in which AGN are associated only with the very last phases of the…