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We report on the X-ray time resolved spectral analysis of XMM-Newton observations of NGC 3783. The main goal is to detect transient features in the Fe K line complex, in order to study the dynamics of the innermost accretion flow. We reanalize archival observations of NGC 3783, a bright local AGN, for which a transient Fe line was reported, complementing this data set with new available observations. This results in a long set of observations which can allow us to better assess the significance of transient features and possibly test their recurrence time. Moreover, since the new data catch the source in an obscured state, this analysis allows also to test whether the appearance/disappearance of transient features is linked to the presence of obscuring gas. We detect discrete features at the >=90% significance level both in emission and in absorption at different times of the observations, split into 5ks time-resolved spectra. The overall significance of individual features is higher in the obscured dataset. The energy distribution of the detections changes between the two states of the source, and the features appear to cluster at different energies. Counting the occurrences of emission/absorption lines at the same energies, we identify several groups of $\geq3\sigma$ detections: emission features in the 4-6 keV band are present in all observations and are most likely due to effects of the absorber present in the source; an emission line blend of neutral Fe K$\beta$/ionized Fe Ka is present in the unobscured dataset; absorption lines produced by gas at different ouflowing velocities and ionization states show an increase in energy between the two epochs, shifting from ~6 keV to ~6.7-6.9 keV. The representation of the features in a time-energy plane via residual maps highlighted a possible modulation of the Fe Ka line intensity, linked to the clumpiness of the absorbing medium., Comment: accepted, A&A

The non-linear relation between the X-ray and ultraviolet (UV) luminosity in quasars has been used to derive quasar distances and to build a Hubble diagram at redshifts up to $z\sim$ 7. This cosmological application is based on the assumption of independence of the relation on redshift and luminosity. We want to test the reliability of this hypothesis by studying the spectroscopic properties of high-redshift quasars in the X-ray and UV bands. We performed a one-by-one analysis of a sample of 130 quasars at $z>$ 2.5 with high-quality X-ray and UV spectroscopic observations. We found that not only the X-ray to UV correlation still holds at these redshifts, but its intrinsic dispersion is as low as 0.12 dex (previous works reached 0.20$-$0.22 dex). For a sample of quasars at $z\sim$ 3 with particularly high-quality observations the dispersion further drops to 0.09 dex, a value entirely accountable for by intrinsic variability and source geometry effects. The composite spectra of these quasars, in both the X-rays and the UV, do not show any difference with respect to the average spectra of quasars at lower redshifts. The absence of any spectral difference between high- and low-$z$ quasars and the tightness of the X-ray to UV relation suggests that no evolutionary effects are present in the relation. Therefore, it can be safely employed to derive quasar distances. Under this assumption, we obtain a measurement of the luminosity distance at $z\sim$ 3 with 15 % uncertainty, and in a 4$\sigma$ tension with the concordance model., Comment: Accepted for publication in Astronomy & Astrophysics Letters, 8 pages, 6 figures

Mid- and far-infrared (IR) photometric and spectroscopic observations are fundamental to a full understanding of the dust-obscured Universe and the evolution of both star formation and black hole accretion in galaxies. In this work, using the specifications of the SPace Infrared telescope for Cosmology and Astrophysics (SPICA) as a baseline, we investigate the capability to study the dust-obscured Universe of mid- and far-IR photometry at 34 and 70 mu m and low-resolution spectroscopy at 17-36 mu m using the state-of-the-art Spectro-Photometric Realisations of Infrared-selected Targets at all-z (SPRITZ) simulation. This investigation is also compared to the expected performance of the Origins Space Telescope and the Galaxy Evolution Probe. The photometric view of the Universe of a SPICA-like mission could cover not only bright objects (e.g. L-IR > 10(12) L-circle dot) up to z = 10, but also normal galaxies (L-IR < 10(11) L-circle dot) up to z similar to 4. At the same time, the spectroscopic observations of such mission could also allow us to estimate the redshifts and study the physical properties for thousands of star-forming galaxies and active galactic nuclei by observing the polycyclic aromatic hydrocarbons and a large set of IR nebular emission lines. In this way, a cold, 2.5-m size space telescope with spectro-photometric capability analogous to SPICA, could provide us with a complete three-dimensional (i.e. images and integrated spectra) view of the dust-obscured Universe and the physics governing galaxy evolution up to z similar to 4.

Obscured AGN represent a significant fraction of the entire AGN population, especially at high redshift (~70% at z=3--5). They are often characterized by the presence of large gas and dust reservoirs that are thought to sustain and possibly obscure vigorous star formation processes that make these objects shine at far-IR and sub-mm wavelengths. We exploit ALMA Cycle 4 observations of the continuum (~2.1mm) and high-J CO emission of a sample of six X-ray selected SMGs hosting an obscured AGN at z_spec>2.5 in the 7 Ms CDF-S. We measured the masses and sizes of the dust and molecular gas and we derived the gas density and column density on the basis of a uniform sphere geometry. Finally, we compared the measured column densities with those derived from the Chandra X-ray spectra. We detected both the continuum and line emission for three sources for which we measured both the flux density and size. For the undetected sources, we derived an upper limit on the flux density. We found that the detected galaxies are rich in gas and dust (molecular gas mass in the range 10^24 cm-2) regime. In addition, we found that all the detected sources show a velocity gradient reminding one rotating system, even though two of them show peculiar features in their morphology that can be associated with a chaotic, possibly merging, structure., Comment: 15 pages, 6 figures, 7 tables. Accepted for publication in A&A

The combination of optical and mid-infrared (MIR) photometry has been extensively used to select red active galactic nuclei (AGNs). Our aim is to explore the obscuration properties of these red AGNs with both X-ray spectroscopy and spectral energy distributions (SEDs). In this study, we re-visit the relation between optical/MIR extinction and X-ray absorption. We use IR selection criteria, specifically the $W1$ and $W2$ WISE bands, to identify 4798 AGNs in the $\it{XMM-XXL}$ area ($\sim 25$deg$^2$). Application of optical/MIR colours ($r- W2 > 6$) reveals 561 red AGNs (14$\%$). Of these, 47 have available X-ray spectra with at least 50 net (background-subtracted) counts per detector. For these sources, we construct SEDs from the optical to the MIR using the CIGALE code. The SED fitting shows that 44 of these latter 47 sources present clear signs of obscuration based on the AGN emission and the estimated inclination angle. Fitting the SED also reveals ten systems ($\sim20\%$) which are dominated by the galaxy. In these cases, the red colours are attributed to the host galaxy rather than AGN absorption. Excluding these ten systems from our sample and applying X-ray spectral fitting analysis shows that up to $76\%$ (28/37) of the IR red AGNs present signs of X-ray absorption. Thus, there are nine sources ($\sim20\%$ of the sample) that although optically red, are not substantially X-ray absorbed. Approximately $50\%$ of these sources present broad emission lines in their optical spectra. We suggest that the reason for this apparent discrepancy is that the r-W2 criterion is sensitive to smaller amounts of obscuration relative to the X-ray spectroscopy. In conclusion, it appears that the majority of red AGNs present considerable obscuration levels as shown by their SEDs. Their X-ray absorption is moderate with a mean of $\rm N_H \sim 10^{22}\, \rm{cm^{-2}}$., A&A accepted, 37 pages, 51 figures, 7 tables

Based on ALMA Band 3 observations of the CO(2-1) line transition, we report the discovery of three new gas-rich (M_H2 ~ 1.5-4.8 x 10^10 M_sun, SFRs in the range ~5-100 M_sun/yr) galaxies in an overdense region at z=1.7, that already contains eight spectroscopically confirmed members. This leads to a total of 11 confirmed overdensity members, within a projected distance of ~ 1.15 Mpc and in a redshift range of Dz = 0.012. Under simple assumptions, we estimate that the system has a total mass of >= 3-6 x 10^13 M_sun, and show that it will likely evolve into a >~ 10^14 M_sun cluster at z = 0. The overdensity includes a powerful Compton-thick Fanaroff-Riley type II (FRII) radio-galaxy, around which we discovered a large molecular gas reservoir (M_H2 ~ 2 x 10^11 M_sun). We fitted the FRII resolved CO emission with a 2-D Gaussian model with major (minor) axis of ~ 27 (~ 17) kpc, that is a factor of ~3 larger than the optical rest-frame emission. Under the assumption of a simple edge-on disk morphology, we find that the galaxy interstellar medium produces a column density towards the nucleus of ~ 5.5 x 10^23 cm^-2. Such a dense ISM may then contribute significantly to the total nuclear obscuration measured in the X-rays (N_(H,X) ~ 1.5 x 10^24 cm^-2) in addition to a small, pc-scale absorber around the central engine. The velocity map of this source unveils a rotational motion of the gas that is perpendicular to the radio-jets. The FRII is located at the center of the projected spatial distribution of the structure members, and its velocity offset from the peak of the redshift distribution is well within the structure's velocity dispersion. All this, coupled with the large amount of gas around the FRII, its stellar mass of ~ 3 x 10^11 M_sun, SFR of ~ 200-600 M_sun/yr, and powerful radio-to-X-ray emission, suggests that this source is the likely progenitor of the future brightest cluster galaxy., 7 pages, 4 figures, 2 tables. Accepted for publication as a Letter in A&A

Aims. The SINFONI survey for Unveiling the Physics and Effect of Radiative feedback (SUPER) was designed to conduct a blind search for AGN-driven outflows on X-ray-selected AGNs at redshift z ∼ 2 with high (∼2 kpc) spatial resolution, and to correlate them with the properties of their host galaxy and central black hole. The main aims of this paper are: (a) to derive reliable estimates for the masses of the black holes and accretion rates for the Type-1 AGNs in this survey; and (b) to characterise the properties of the AGN-driven winds in the broad line region (BLR). Methods. We analysed rest-frame optical and UV spectra of 21 Type-1 AGNs. We used Hα, Hβ, and MgII line profiles to estimate the masses of the black holes. We used the blueshift of the CIV line profile to trace the presence of winds in the BLR. Results. We find that the Hα and Hβ line widths are strongly correlated, as is the line continuum luminosity at 5100 Å with Hα line luminosity, resulting in a well-defined correlation between black hole masses estimated from Hα and Hβ. Using these lines, we estimate that the black hole masses for our objects are in the range Log (MBH/M⊙) = 8.4–10.8 and are accreting at λEdd = 0.04–1.3. Furthermore, we confirm the well-known finding that the CIV line width does not correlate with the Balmer lines and the peak of the line profile is blueshifted with respect to the [OIII]-based systemic redshift. These findings support the idea that the CIV line is tracing outflowing gas in the BLR for which we estimated velocities up to ∼4700 km s−1. We confirm the strong dependence of the BLR wind velocity on the UV-to-X-ray continuum slope, the bolometric luminosity, and Eddington ratio. We infer BLR mass outflow rates in the range 0.005–3 M⊙ yr−1, revealing a correlation with the bolometric luminosity consistent with that observed for ionised winds in the narrow line region (NLR), and X-ray winds detected in local AGNs, and kinetic power ∼10−7 − 10−4 × LBol. The coupling efficiencies predicted by AGN-feedback models are much higher than the values reported for the BLR winds in the SUPER sample; although it should be noted that only a fraction of the energy injected by the AGN into the surrounding medium is expected to become kinetic power in the outflow. Finally, we find an anti-correlation between the equivalent width of the [OIII] line and the CIV velocity shift, and a positive correlation between this latter parameter and [OIII] outflow velocity. These findings, for the first time in an unbiased sample of AGNs at z ∼ 2, support a scenario where BLR winds are connected to galaxy-scale detected outflows, and are therefore capable of affecting the gas in the NLR located at kiloparsec scale distances. We thank the anonymous referee for the useful comments that improved the paper. The scientific results reported in this article are based on observations collected at the European organisation for Astronomical Research in the Southern Hemisphere under ESO programs 196.A-0377 (SINFONI data) and LP175.A-0839 (zCOSMOS data), and SDSS. Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the US Department of Energy Office of Science. The SDSS-III web site is http://www.sdss3.org/. SDSS-III is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS-III Collaboration including the University of Arizona, the Brazilian Participation Group, Brookhaven National Laboratory, Carnegie Mellon University, University of Florida, the French Participation Group, the German Participation Group, Harvard University, the Instituto de Astrofisica de Canarias, the Michigan State/Notre Dame/JINA Participation Group, Johns Hopkins University, Lawrence Berkeley National Laboratory, Max Planck Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, New Mexico State University, New York University, Ohio State University, Pennsylvania State University, University of Portsmouth, Princeton University, the Spanish Participation Group, University of Tokyo, University of Utah, Vanderbilt University, University of Virginia, University of Washington, and Yale University. This research project was supported by the DFG Cluster of Excellence “Origin and Structure of the Universe” (universe-cluster.de). G. V. acknowledges financial support from Premiale 2015 MITic (PI B. Garilli). G. C., M. Bi, C. F. and F. F. acknowledge support from PRIN MIUR project “Black Hole winds and the Baryon Life Cycle of Galaxies: the stone-guest at the galaxy evolution supper”, contract #2017PH3WAT. M. P. is supported by the Programa Atracción de Talento de la Comunidad de Madrid via grant 2018-T2/TIC-11715.. With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737) Peer review

The SINFONI survey for Unveiling the Physics and Effect of Radiative feedback (SUPER) was designed to conduct a blind search for AGN-driven outflows on X-ray selected AGN at redshift z$\sim$2 with high ($\sim$2 kpc) spatial resolution, and correlate them to the properties of the host galaxy and central black hole. The main aims of this paper are: a) to derive reliable estimates for the BH mass and accretion rates for the Type-1 AGN in this survey; b) to characterize the properties of the AGN driven winds in the BLR. We analyzed rest-frame optical and UV spectra of 21 Type-1 AGN. We found that the BH masses estimated from H$\alpha$ and H$\beta$ lines are in agreement. We estimate BH masses in the range Log(M$\rm_{BH}/M_{\odot}$)=8.4-10.8 and Eddington ratios $\rm\lambda_{Edd}$ =0.04-1.3. We confirm that the CIV line width does not correlate with the Balmer lines and the peak of the line profile is blue-shifted with respect to the [OIII]-based systemic redshift. These findings support the idea that the CIV line is tracing outflowing gas in the BLR, with velocities up to $\sim$4700 km/s. We confirm the strong dependence of the BLR wind velocity with the UV-to-Xray continuum slope, L$\rm_{Bol}$ and $\rm\lambda_{Edd}$. We inferred BLR mass outflow rates in the range 0.005-3 M$_{\odot}$/yr, showing a correlation with the bolometric luminosity consistent with that observed for ionized winds in the NLR and X-ray winds detected in local AGN, and kinetic power $\sim$10$^{[-7:-4]}\times$ L$\rm_{Bol}$. Finally, we found an anti-correlation between the equivalent width of the [OIII] line with respect to the CIV shift, and a positive correlation with [OIII] outflow velocity. These findings, for the first time in an unbiased sample of AGN at z$\sim$2, support a scenario where BLR winds are connected to galaxy scale detected outflows, and are capable of affecting the gas in the NLR located at kpc scale., Comment: Accepted for publication in A&A

We present X-ray spectra of 185 bright sources detected in the XMM-Newton deep survey of the Chandra Deep Field South, combining the three EPIC cameras. The 2-10 keV flux limit of the sample is 2e-15 erg/s/cm2. The sources are distributed over a redshift range of z=0.1-3.8. Eleven new X-ray redshift measurements are included. A spectral analysis was performed using a simple model to obtain absorbing column densities, rest-frame 2-10 keV luminosities and Fe K line properties of 180 sources at z>0.4. Obscured AGN are found to be more abundant toward higher redshifts. Using the XMM-Newton data alone, seven Compton-thick AGN candidates are identified, which makes the Compton-thick AGN fraction to be ~4%. An exploratory spectral inspection method with two rest-frame X-ray colours and an Fe line strength indicator is introduced and tested against the results from spectral fitting. This method works reasonably well to characterise a spectral shape and can be useful for a pre-selection of Compton-thick AGN candidates. We found six objects exhibiting broad Fe K lines out of 21 unobscured AGN of best data quality, implying a detection rate of ~30%. Five redshift spikes, each of which has more than six sources, are identified in the redshift distribution of the X-ray sources. Contrary to the overall trend, the sources at the two higher-redshift spikes at z=1.61 and z=2.57 have puzzlingly low obscuration., Accepted for publication in Astronomy & Astrophysics. Table 1 and Fig. 2 are available in electronic form the CDS. Typos corrected and some language editing and references added

A tight non-linear relation between the X-ray and the optical-ultraviolet (UV) emission has been observed in active galactic nuclei (AGN) over a wide range of redshift and several orders of magnitude in luminosity, suggesting the existence of an ubiquitous physical mechanism regulating the energy transfer between the accretion disc and the X-ray emitting corona. Recently, our group developed a method to use this relation in observational cosmology, turning quasars into standardizable candles. This work mainly seeks to investigate the potential evolution of this correction at high redshifts. We thus studied the LX − LUV relation for a sample of quasars in the redshift range 4 < z < 7, adopting the selection criteria proposed in our previous work regarding their spectral properties. The resulting sample consists of 53 type 1 (unobscured) quasars, observed either with Chandra or XMM-Newton, for which we performed a full spectral analysis, determining the rest-frame 2 keV flux density, as well as more general X-ray properties such as the estimate of photon index, and the soft (0.5–2 keV) and hard (2–10 keV) unabsorbed luminosities. We find that the relation shows no evidence for evolution with redshift. The intrinsic dispersion of the LX–LUV for a sample free of systematics/contaminants is of the order of 0.22 dex, which is consistent with previous estimates from our group on quasars at lower redshift.

arXiv:1710.02356v1, A far-infrared observatory such as the SPace Infrared telescope for Cosmology and Astrophysics, with its unprecedented spectroscopic sensitivity, would unveil the role of feedback in galaxy evolution during the last 10 Gyr of the Universe (z = 1.5-2), through the use of far- and mid-infrared molecular and ionic fine structure lines that trace outflowing and infalling gas. Outflowing gas is identified in the far-infrared through P-Cygni line shapes and absorption blueshifted wings in molecular lines with high dipolar moments, and through emission line wings of fine-structure lines of ionised gas. We quantify the detectability of galaxy-scale massive molecular and ionised outflows as a function of redshift in AGN-dominated, starburst-dominated, and main-sequence galaxies, explore the detectability of metal-rich inflows in the local Universe, and describe the most significant synergies with other current and future observatories that will measure feedback in galaxies via complementary tracers at other wavelengths., EGA is a Research Associate at the Harvard–Smithsonian Center for Astrophysics, and thanks the Spanish Ministerio de Economía y Competitividad for support under projects FIS2012-39162-C06-01 and ESP2015-65597-C4-1-R. EGA and JF acknowledge support under NASA grant ADAP NNX15AE56G. Basic research in IR astronomy at NRL is funded by the US ONR. FJC acknowledges financial support through grant AYA2015- 64346-C2-1-P (MINECO/FEDER).

(abridged) We present the X-ray analysis of a sample of 30 luminous quasars at $z\simeq3.0-3.3$ with deep XMM-Newton observations, selected from the SDSS-DR7 to be representative of the most luminous, intrinsically blue quasar population. By construction, the sample boasts a unique degree of homogeneity in terms of optical/UV properties. In the X-rays, only four sources are too faint for a detailed spectral analysis. Neglecting a radio-loud object, the other 25 quasars are, as a whole, the most X-ray luminous ever observed, with rest-frame 2-10 keV luminosities of $0.5-7\times10^{45}$ erg/s. The continuum photon index distribution, centred at $��\sim1.85$, is in excellent agreement with those in place at lower redshift, luminosity and black-hole mass, confirming the universal nature of the X-ray emission mechanism in quasars. Even so, when compared against the well-known $L_{\rm X}-L_{\rm UV}$ correlation, our quasars unexpectedly split into two distinct subsets. About 2/3 of the sources are clustered around the relation with a minimal scatter of 0.1 dex, while the remaining 1/3 appear to be X-ray underluminous by factors of $>3-10$. Such a large incidence ($\approx25\%$) of X-ray weakness has never been reported in radio-quiet, non-BAL quasar samples. Several factors could contribute to enhance the X-ray weakness fraction among our $z\simeq3$ blue quasars. However, the X-ray weak objects also have, on average, flatter spectra, with no clear evidence of absorption. Indeed, column densities in excess of a few $\times10^{22}$ cm$^{-2}$ can be ruled out for most of the sample. We suggest that, at least in some of our X-ray weak quasars, the corona might experience a radiatively inefficient phase due to the presence of a powerful accretion-disc wind, which substantially reduces the accretion rate through the inner disc and so the availability of seed photons for Compton up-scattering., Version accepted for publication in Astronomy & Astrophysics (13+2 pages, 10+1 figures, 3 tables)

More than 200 quasars (QSOs) with spectroscopic redshift z > 6 have been discovered so far. Multi-wavelength observations showed that these QSOs are evolved systems with large black hole masses (108−10M⊙), and their broad-band spectral energy distributions (SEDs) and rest-frame NIR/optical/UV spectra have not significantly evolved over cosmic time. The formation of their Super Massive Black Holes in less than 1 Gyr is still a challenge for theory, with many simulations claiming they formed at the center of primordial overdense regions. I report the study of all the 29 z∼6 QSOs observed so far with X-rays, in which our group concluded that the X-ray spectral properties of high-z QSOs do not differ significantly from those of QSOs at lower-z. We also obtained a deep 500 ks Chandra observation to study the environment around the QSO J1030+0524, which shows the best evidence of an overdense region around a z∼6 QSO. This is the deepest X-ray observation ever achieved for a z∼6 QSO. Comparing our results with those from previous XMM observation we found a hardening of the X-ray spectrum and a decrease of the flux by a factor 2.5. This is the first evidence of a variable QSO at such high redshift. I also report the discovery of a diffuse X-ray emission southward the QSO, that could be linked to the feedback of the AGN.

The dynamics and geometry of the material close to the SMBH in AGN are still largely uncertain, both as regards the inflows via accretion disk and the outflows.The latter phenomena may have a fundamental role in the AGN feedback on the host galaxy, so it is important to understand their properties and extent. A simultaneous investigation of inflows and outflows may highlight some kind of correlation, that shall help to unravel the driving mechanisms of massive winds from the disk, still an open issue. Time-resolved spectral analysis is a key tool to investigate these phenomena.The 4.0-10.0 keV energy band is the most suitable for these aims, because it includes the Fe Kα fluorescence emission line at 6.4 keV, a fundamental proxy of the motions around the SMBH, and possibly Fe resonant absorption lines, features that indicate the presence of massive, relativistic (∼0.1c) disk winds (Ultra Fast Outflows, Tombesi et al. 2010), observed in about 50% of local AGN for which good quality data exist. We use a technique, Residual maps, that couples time and spectral analysis to the two X-ray brightest Seyfert 1 observed to date: NGC 3783 and Mrk 509. It allows to identify spectral features and trace their evolution in time. Residual maps can be used to detect potentially interesting time intervals, on which a deep spectral analysis can be (and will be) carried out to characterize the physical phenomena in act.

Deep X surveys are an essential tool for the study of obscured AGN. These objects are very faint even in the X-ray band, due to the large column densities responsible for the obscuration. We studied obscured AGN candidates in the deep field around the z=6.31 QSO SDSS J1030+0524. The goal of this project is the selection and characterization of obscured AGN using a multi-wavelength approach. We used X-ray spectral features such as 6.4 keV Fe line or Fe absorption edge to estimate the still unknown redshift of these sources from the X-ray band, and compared the results with the outcomes of a standard SED-fitting procedure (hyperz code, Bolzonella+00) using optical/NIR/MIR photometry. The obtained results show the possibility to use X-ray spectra in support in the search for redshift of obscured AGN.

Out of the known gravitationally lensed systems, Q2235+0305 (the Einstein Cross) is perhaps the most studied, due to its brightness/vicinity and configuration (quasar at redshift z=1.695, lensing galaxy at z=0.0305). This system shows both macrolensing and microlensing effects, which offer a unique tool to investigate the innermost structure of the quasar. I present the preliminary results obtained analyzing thirty-five observations carried out over the last seventeen years by Chandra, and three XMM-Newton observations, among which only one has been published so far. The aim of this work is to study the X-ray variability of the quasar, investigate the regions where the high-energy photons originate and how they interact with the matter surrounding the black hole. &nbsp

We report on the status of on-going, deep multi-band observations inthe field around the z=6.31 QSO SDSS J1030+0524, where an overdensityof candidate Lyman Break Galaxies at the QSO redshift was found. Theobservations include a large program with Chandra, deep JVLAobservations, and a strategic LBT program for opticalspectroscopy.Additional imaging and spectroscopic coverage isprovided, among others, by HST, VLT/MUSE, Keck and Spitzer data. The J1030 field is currently the 4th deepest X-ray survey, one of thefew radio fields observed at microJy depth, and the only deepmulti-bandsurvey in a highly biased region of the early Universe. We are collecting and organizing all multi-band data in a publicdatabase that can be effectively exploited by the AGN community. Examples of preliminary results from these data include: i) the firstspectroscopic confirmation of a few galaxies at the redshift of SDSSJ1030+0524, and ii) the discovery of a proto-cluster at z=1.7 around aCompton-thick FRII radio-galaxy.

I will review the most important results from near-IR spectroscopic observations of WISE/SDSS selected hyper-luminous (WISSH) quasars, designed to accurately probe the role of nuclear activity in SMBH-galaxy self-regulated growth via extended outflows. The total sample consists of 90 broad-line quasars at the brightest end of theAGNluminosity function (L_bol > 1014 L_sun) and at the peak of their number density (z ~ 2.5 - 3.5). We found that WISSH quasars are typically powered by highly accreting (0.3-3 Ledd), ten billion solar masses SMBHs, demonstrating that WISSH provides a simple and valuable tool to complete the census of the extreme SMBH population in the Universe. The huge luminosity drives very powerful winds both at BLR and NLR scales. We discovered [OIII] emission lines with a broad profile, tracing ionized outflows with kinetic power up to ~4% of L_bol in ~30% of the sample.Remarkably, the remaining 70% of quasars lacks [OIII] emission but shows strong winds traced by 3,000-8,000 km/s blueshifts of the CIV broad emission line, revealing strong radiatively driven winds that dominate the BLR kinematics. Finally, I will discuss nuclear and outflows properties of WISSH quasars in terms of inclination angle and fundamentalAGNparameters such as bolometric luminosity, SMBH mass, Eddington ratio and the shape of the UV-X-ray continuum.

Deep X-ray surveys provide unprecedented access to the population of accreting super-massive black holes (SMBH) at high redshift. I will present our recent results (Vito et al. 2018) on the 33 AGN. I will show our findings on the high-redshift AGN X-ray luminosity function, focussing in particular on the slope of the faint end, accessible only by the deepest X-ray surveys. This is particularly important to assess the contribution of AGN to the cosmic reionization. All of these results will be placed in the context of SMBH seeds formation and growth. I will also discuss how future missions like Lynx, Athena and JWST will boost our knowledge of the SMBH formation and evolution in the early Universe.

Submillimeter Galaxies (SMGs) at high redshift are among the best targets to investigate the early evolutionary phases in the lifetime of massive systems, during which large gas reservoirs sustain vigorous star formation and efficiently feed the central, buried Super Massive Black Hole (SMBH), until it enters into luminous Quasar (QSO) phase, quenching the star formation. I present the analysis of new ALMA band 4 (1.8-2.4 mm) data of six obscured QSOs (log NH > 23) hosted by SMGs at redshift > 2.5 in the 7 Ms Chandra Deep Field South (CDF-S), showing their properties in terms of continuum dust emission and high-J CO transitions. Sizes and masses of the galaxies are measured to estimate whether and to which extent the host ISM may contribute to the nuclear absorption, assuming different geometries. The derived column densities suggest that the galaxy ISM can substantially contribute to the AGN obscuration. I also discuss the kinematics and morphology in some of these object, finding that two of the sources present unambiguous features of a rotating system, while a third source is possibly undergoing a merger.

The standard QSO-galaxy co-evolutionary scenario predicts a phase of deeply "buried" supermassive black hole growth coexisting with a starburst (SB) before feedback phenomena deplete the cold molecular gas reservoir of the galaxy and an optically luminous QSO is revealed ("SB-QSO evolutionary sequence"). We tested simple SB-QSO paradigm predictions by comparing the molecular (carbon monoxide, CO) gas properties of 56 obscured and 49 unobscured QSO host galaxies at high-redshift (z~1-6) with those of ~ 170 high-z star forming galaxies from the literature. We found that, on average, obscured AGN at z >1 are associated with higher star formation efficiencies (SFEs) and lower gas fractions with respect to normal star forming galaxies and SBs at given stellar mass and redshift. These results could suggest that their cold gas content has been already depleted by powerful AGN-driven outflows. Moreover, we did not find any clear separation between the properties of unobscured and obscured QSOs (e.g. they have similar SFEs), suggesting a scenario where feedback can rapidly impact the host galaxy evolution.

The mid-infrared (IR) range contains many spectral features associated with large molecules and dust grains such as polycyclic aromatic hydrocarbons (PAHs) and silicates. These are usually very strong compared to fine-structure gas lines, and thus valuable in studying the spectral properties of faint distant galaxies. In this paper, we evaluate the capability of low-resolution mid-IR spectroscopic surveys of galaxies that could be performed by SPICA. The surveys are designed to address the question how star formation and black hole accretion activities evolved over cosmic time through spectral diagnostics of the physical conditions of the interstellar/circumnuclear media in galaxies. On the basis of results obtained with Herschel far-IR photometric surveys of distant galaxies and Spitzer and AKARI near- to mid-IR spectroscopic observations of nearby galaxies, we estimate the numbers of the galaxies at redshift z > 0.5, which are expected to be detected in the PAH features or dust continuum by a wide (10 deg^2) or deep (1 deg^2) blind survey, both for a given observation time of 600 hours. As by-products of the wide blind survey, we also expect to detect debris disks, through the mid-IR excess above the photospheric emission of nearby main-sequence stars, and we estimate their number. We demonstrate that the SPICA mid-IR surveys will efficiently provide us with unprecedentedly large spectral samples, which can be studied further in the far-IR with SPICA., Paper accepted for publication on PASA on 18th October 2017, as part of the SPICA Special Issue

Context. The XMM-XXL survey uses observations from XMM-Newton to detect clusters of galaxies over a wide range in mass and redshift. The moderate PSF of XMM-Newton means that point sources within or projected onto a cluster may not be separated from the cluster emission, leading to enhanced luminosities and affecting the selection function of the cluster survey. Aims. We present the results of short Chandra observations of 21 galaxy clusters and cluster candidates at redshifts z $>$ 1 detected in the XMM-XXL survey in X-rays or selected in the optical and infra-red. Methods. With the superior angular resolution of Chandra we investigate whether there are any point sources within the cluster region that were not detected by the XMM-XXL analysis pipeline, and whether any point sources were misclassified as distant clusters. Results. Of the 14 X-ray selected clusters, nine are free from significant point source contamination, either having no previously unresolved sources detected by Chandra, or with less than about 10% of the reported XXL cluster flux being resolved into point sources. Of the other five sources, one is significantly contaminated by previously unresolved AGN, and four appear to be AGN misclassified as clusters. All but one of these cases are in the subset of less secure X-ray selected cluster detections and the false positive rate is consistent with that expected from the XXL selection function modelling. We also considered a further seven optically-selected cluster candidates associated with faint XXL sources that were not classed as clusters. By decontaminating and vetting these distant clusters, we provide a pure sample of clusters at redshift z $>$ 1 for deeper follow-up observations, and demonstrate the utility of using Chandra snapshots to test for AGN in surveys with high sensitivity but poor angular resolution.

Aims. We show how the XXL multiwavelength survey can be used to shed light on radio galaxies and their environment. Methods. Two prominent radio galaxies were identified in a visual examination of the mosaic of XXL-North obtained with the Giant Metrewave Radio Telescope at 610 MHz. Counterparts were searched for in other bands. Spectroscopic redshifts from the GAMA database were used to identify clusters and/or groups of galaxies, estimate their masses with the caustic method, and quantify anisotropies in the surrounding galaxy distribution via a Fourier analysis. Results. Both radio galaxies are of FR I type and are hosted by early-type galaxies at a redshift of 0.138. The first radio source, named the Exemplar, has a physical extent of ~400 kpc ; it is located in the cluster XLSSC 112, which has a temperature of ~2 keV, a total mass of ~10^14 M⊙, and resides in an XXL supercluster with eight known members. The second source, named the Double Irony, is a giant radio galaxy with a total length of about 1.1 Mpc. Its core coincides with a cataloged point-like X-ray source, but no extended X-ray emission from a surrounding galaxy cluster was detected. However, from the optical data we determined that the host is the brightest galaxy in a group that is younger, less virialized, and less massive than the Exemplar’s cluster. A friends-of-friends analysis showed that the Double Irony’s group is a member of the same supercluster as the Exemplar. There are indications that the jets and plumes of the Double Irony have been deflected by gas associated with the surrounding galaxy distribution. Another overdensity of galaxies (the tenth) containing a radio galaxy was found to be associated with the supercluster. Conclusions. Radio Galaxies can be used to find galaxy clusters/groups that are below the current sensitivity of X-ray surveys.

We present a multi-wavelength study of IC 1531 (z=0.02564), an extragalactic radio source associated with the $��$-ray object 3FGL J0009.9-3206 and classified as a blazar of uncertain type in the Third Fermi Large Area Telescope AGN Catalog (3LAC). A core-jet structure, visible in radio and X-rays, is enclosed within a $\sim$220 kpc wide radio structure. The morphology and spectral characteristics of the kiloparsec jet in radio and X-rays are typical of Fanaroff-Riley type I galaxies. The analysis of the radio data and optical spectrum and different diagnostic methods based on the optical, infrared and $��$-ray luminosities also support a classification as a low-power radio galaxy seen at moderate angles ($��=$10$^\circ$-20$^\circ$). In the framework of leptonic models, the high-energy peak of the non-thermal nuclear spectral energy distribution can be explained in terms of synchrotron-self-Compton emission from a jet seen at $��\sim$15$^\circ$. Similarly to other misaligned AGNs detected by Fermi, the required bulk motion is lower ($��_{\rm bulk}=$4) than the values inferred in BL Lac objects, confirming that, because of the de-boosting of emission from the highly-relativistic blazar region, these nearby systems are valuable targets to probe the existence of multiple sites of production of the most energetic emission in the jets., 11 pages, 4 figures

IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.

IR spectroscopy in the range 12-230 micron with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes that govern the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope (JWST) and the new generation of Extremely Large Telescopes (ELTs) at shorter wavelengths and the Atacama Large Millimeter Array (ALMA) at longer wavelengths. SPICA, with its 2.5-m telescope actively-cooled to below 8K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei (AGN), sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. AGN and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. SPICA's large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z~6. Furthermore, SPICA spectroscopy will uncover the most luminous galaxies in the first few hundred million years of the Universe, through their characteristic dust and molecular hydrogen features.

We present VLT/X-Shooter and MUSE spectroscopy of a faint F814W = 28.60 ± 0.33 ({M}{UV}=-17.0), low-mass (≲{10}7{M}☉ ), and compact (R eff = 62 pc) freshly star-forming galaxy at z = 3.1169 magnified (16×) by the Hubble Frontier Fields galaxy cluster Abell S1063. Gravitational lensing allows for a significant jump toward low-luminosity regimes, in moderately high-resolution spectroscopy (R=λ /dλ ∼ 3000{--}7400). We measured C IV λ 1548,1550, He II λ 1640, O III]λ 1661,1666, C III]λ λ 1907,1909, Hβ, [O III]λ λ 4959,5007 emission lines with {FWHM}≲ 50 km s-1 and (de-lensed) fluxes spanning the interval 1.0× {10}-19{--}2× {10}-18 erg s-1 cm-2 at signal-to-noise ratio (S/N) = 4-30. The double-peaked Lyα emission with {{∆ }}v({red}-{blue})=280(±7) km s-1 and de-lensed fluxes {2.4}({blue)}| {8.5}({red)}× {10}-18 erg s-1 cm-2 (S/N = {38}({blue)}| {110}({red)}) indicate a low column density of neutral hydrogen gas consistent with a highly ionized interstellar medium as also inferred from the large [O III]λ 5007/ [O II]λ 3727 \gt \quad 10 ratio. We detect C IV λ 1548,1550 resonant doublet in emission, each component with {FWHM}≲ 45 km s-1 and redshifted by +51(±10) km s-1 relative to the systemic redshift. We interpret this as nebular emission tracing an expanding optically thin interstellar medium. Both C IV λ 1548,1550 and He II λ 1640 suggest the presence of hot and massive stars (with a possible faint active galactic nucleus). The ultraviolet slope is remarkably blue, β =-2.95+/- 0.20 ({F}λ ={λ }β ), consistent with a dust-free and young ≲20 Myr galaxy. Line ratios suggest an oxygen abundance 12 + log(O/H)\quad \lt \quad 7.8. We are witnessing an early episode of star formation in which a relatively low N H I and negligible dust attenuation might favor a leakage of ionizing radiation. This galaxy currently represents a unique low-luminosity reference object for future studies of the reionization epoch with the James Webb Space Telescope. Based on observations collected at the European Southern Observatory for Astronomical research in the Southern Hemisphere under ESO programs P095.A-0840, P095.A-0653, P186.A-0798.

Type 2 active galactic nuclei (AGN) represent the majority of the AGN population. However, due to the difficulties in measuring their black hole (BH) masses, it is still unknown whether they follow the same BH mass-host galaxy scaling relations valid for quiescent galaxies and type 1 AGN. Here we present the locus of type 2 AGN having virial BH mass estimates in the $M_{BH}-\sigma_\star$ plane. Our analysis shows that the BH masses of type 2 AGN are $\sim0.9$ dex smaller than type 1 AGN at $\sigma_\star\sim 185$ km s$^{-1}$, regardless of the (early/late) AGN host galaxy morphology. Equivalently, type 2 AGN host galaxies have stellar velocity dispersions $\sim 0.2$ dex higher than type 1 AGN hosts at $M_{BH}\sim10^7$ M$_\odot$., Comment: 6 pages, 3 figures, accepted for publication in MNRAS Letters

A WISE/SDSS-selected hyper-luminous quasar (WISSH) survey study on the BLR and galaxy scale winds

We present the 78 ks $\textit{Chandra}$ observations of the $\textit{z}$ = 6.4 quasar SDSS J1148+5251. The source is clearly detected in the energy range 0.3–7 keV with 42 counts (with a significance ≳9σ). The X-ray spectrum is best fitted by a power law with photon index Γ = 1.9 absorbed by a gas column density of N$_{H}$=2.0$^{+2.0}_{−1.5}$ %. We measure an intrinsic luminosity at 2–10 and 10–40 keV equal to ∼ 1.5 × 10$^{45}$ erg s$^{-1}$, comparable with luminous local and intermediate-redshift quasar properties. Moreover, the X-ray to optical power-law slope value (αOX = −1.76 ± 0.14) of J1148 is consistent with the one found in quasars with similar rest-frame 2500 Å luminosity ($\textit{L}$2500 ∼ 10$^{32}$ erg s$^{-1}$ Å$^{-1}$). Then we use $\textit{Chandra}$ data to test a physically motivated model that computes the intrinsic X-ray flux emitted by a quasar starting from the properties of the powering black hole and assuming that X-ray emission is attenuated by intervening, metal-rich (Z ≥ Z⊙) molecular clouds (MC) distributed on ∼kpc scales in the host galaxy. Our analysis favours a black hole mass MBH ∼ 3 × 10$^{9}$ M⊙ and a molecular hydrogen mass M$_{H2}$∼2×10$^{10}$ M⊙, in good agreement with estimates obtained from previous studies. We finally discuss strengths and limits of our analysis., RM acknowledges support from the ERC Advanced Grant 695671 ‘QUENCH’ and the Science and Technology Facilities Council (STFC).

We present a systematic analysis of X-ray archival data of all the 29 quasars (QSOs) at $z$ > 5.5 observed so far with Chandra, XMM-Newton and Swift-XRT, including the most-distant quasar ever discovered, ULAS J1120+0641 ($z$ = 7.08). This study allows us to place constraints on the mean spectral properties of the primordial population of luminous Type 1 (unobscured) quasars. Eighteen quasars are detected in the X-ray band, and we provide spectral-fitting results for their X-ray properties, while for the others we provide upper limits to their soft (0.5-2.0 keV) X-ray flux. We measured the power-law photon index and derived an upper limit to the column density for the five quasars (J1306+0356, J0100+2802, J1030+0524, J1148+5251, J1120+0641) with the best spectra (> 30 net counts in the 0.5-7.0 keV energy range) and find that they are consistent with values from the literature and lower-redshift quasars. By stacking the spectra of ten quasars detected by Chandra in the redshift range 5.7 $\le$ $z$ $\le$ 6.1 we find a mean X-ray power-law photon index of $\Gamma = 1.92_{-0.27}^{+0.28}$ and a neutral intrinsic absorption column density of $N_H \le 10^{23}$ cm$^{-2}$. These results suggest that the X-ray spectral properties of luminous quasars have not evolved up to $z$ $\approx$ 6. We also derived the optical-X-ray spectral slopes ($\alpha_{ox}$) of our sample and combined them with those of previous works, confirming that $\alpha_{ox}$ strongly correlates with UV monochromatic luminosity at 2500 \AA . These results strengthen the non-evolutionary scenario for the spectral properties of luminous active galactic nuclei (AGN)., Comment: 12 pages, 7 figures, accepted for publication in Astronomy and Astrophysics

The coeval AGN and galaxy evolution and the observed local relations between SMBHs and galaxy properties suggest some connection or feedback between SMBH growth and galaxy build-up. We looked for correlations between properties of X-ray detected AGN and their FIR detected host galaxies, to find quantitative evidences for this connection, highly debated in the latest years. We exploit the rich multi-wavelength data set available in the COSMOS field for a large sample (692 sources) of AGN and their hosts, in the redshift range $0.1, Comment: 13 pages, 11 fugures, accepted for publication in A&A

Type 2 active galactic nuclei (AGN) represent the majority of the AGN population. However, due to the difficulties in measuring their black hole (BH) masses, it is still unknown whether they follow the same BH mass-host galaxy scaling relations valid for quiescent galaxies and type 1 AGN. Here we present the locus of type 2 AGN having virial BH mass estimates in the $M_{BH}-��_\star$ plane. Our analysis shows that the BH masses of type 2 AGN are $\sim0.9$ dex smaller than type 1 AGN at $��_\star\sim 185$ km s$^{-1}$, regardless of the (early/late) AGN host galaxy morphology. Equivalently, type 2 AGN host galaxies have stellar velocity dispersions $\sim 0.2$ dex higher than type 1 AGN hosts at $M_{BH}\sim10^7$ M$_\odot$., 6 pages, 3 figures, accepted for publication in MNRAS Letters

We present the measurement of the projected and redshift space 2-point correlation function (2pcf) of the new catalog of Chandra COSMOS-Legacy AGN at 2.9$\leq$z$\leq$5.5 ($\langle L_{bol} \rangle \sim$10$^{46}$ erg/s) using the generalized clustering estimator based on phot-z probability distribution functions (Pdfs) in addition to any available spec-z. We model the projected 2pcf estimated using $��_{max}$ = 200 h$^{-1}$ Mpc with the 2-halo term and we derive a bias at z$\sim$3.4 equal to b = 6.6$^{+0.60}_{-0.55}$, which corresponds to a typical mass of the hosting halos of log M$_h$ = 12.83$^{+0.12}_{-0.11}$ h$^{-1}$ M$_{\odot}$. A similar bias is derived using the redshift-space 2pcf, modelled including the typical phot-z error $��_z$ = 0.052 of our sample at z$\geq$2.9. Once we integrate the projected 2pcf up to $��_{max}$ = 200 h$^{-1}$ Mpc, the bias of XMM and \textit{Chandra} COSMOS at z=2.8 used in Allevato et al. (2014) is consistent with our results at higher redshift. The results suggest only a slight increase of the bias factor of COSMOS AGN at z$\gtrsim$3 with the typical hosting halo mass of moderate luminosity AGN almost constant with redshift and equal to logM$_h$ = 12.92$^{+0.13}_{-0.18}$ at z=2.8 and log M$_h$ = 12.83$^{+0.12}_{-0.11}$ at z$\sim$3.4, respectively. The observed redshift evolution of the bias of COSMOS AGN implies that moderate luminosity AGN still inhabit group-sized halos at z$\gtrsim$3, but slightly less massive than observed in different independent studies using X-ray AGN at z$\leq2$., Accepted for publication in The Astrophysical Journal

We exploit the new 7 Ms Chandra observations in the CDF-S, the deepest X-ray survey to date, coupled with CANDELS/GOODS- S data, to measure the total X-ray emission arising from ~2000 galaxies at 3.5 < z < 6.5. This aim is achieved by stacking the Chandra data at the positions of optically selected galaxies, reaching effective exposure times of >=10^9 s. We detect X-ray emission from z ‚ào 4 galaxies at 3 ‚àí 5sigma, while no significant signal is detected from galaxies at higher redshifts. The stacking results are used to estimate the black hole accretion rate density (BHAD) and star -formation rate density (SFRD) at high redshift, assuming a range of prescriptions for X-ray emission due to X-ray binaries. We find that X-ray emission from our sample is likely dominated by processes related to star formation. Our results show that low-rate mass accretion onto SMBHs in individually X-ray-undetected galaxies is negligible, compared with the BHAD measured for samples of X-ray detected AGN, for cosmic SMBH mass assembly at high redshift. We also place, for the first time, constraints on the faint-end of the AGN X- ray luminosity function (logLX ‚ào 42) at z > 4, with evidence for fairly flat slopes.

We present a multi-scale and multi-frequency study of the radio galaxy IC1531 (z=0.026) with Chandra, XMM-Newton and Fermi. The Chandra image shows an X-ray core and 5 extended emission with the radio jet. The X-ray spectrum of the core is well fitted by a power law (Γ=2.2). The X-ray emission of the large scale jet is most-likely synchrotron emission, further confirming the low-power source classication. The gamma-ray analisys shows a 5-days variability, from which it is possible to estimate the size of the emitting region. We present a study of the spectral energy distribution of the core of IC1531 from radio to gamma-ray emission. The models allowed us to determine the nature of the gamma-ray emission and infer the jet kinetic power at sub-pc scales. The jet power at kpc scales is estimated from the total radio luminosity at 151 MHz. Finally, we compare the jet power with the disk luminosity. We discuss our results in terms of the formation and evolution of the jet.

The physics and demographics of high redshift obscured active galactic nuclei is still scarcely studied, and new samples of such objects, selected with different techniques, can provide useful insights into their physical nature. A sample of 90 narrow-line with 1.5< z < 3.0 was selected from the zCOSMOS-deep galaxy sample by detection of the high-ionization CIV 1549A emission line. The presence of this feature in a galaxy spectrum is indicative of nuclear activity, and the selection effectiveness has been also confirmed by ultraviolet emission line diagnostic diagrams. Taking advantage of the large amount of data available in the COSMOS field, the properties of the \civ-selected Type 2 AGN were analyzed, focusing on their host galaxies, X-ray emission, and UV emission line characteristics. Finally, the physical properties of the ionized gas in the Narrow Line Region have been investigated, combining the analysis of strong UV emission lines with the prediction from photoionization models.

(On behalf of the WISSH collaboration) The WISE/SDSS-selected hyper-luminous quasar (WISSH) survey is an extensive multi-band observing program to investigate the role of nuclear activity in SMBH-galaxy self-regulated growth via extended outflows. Our ongoing project is designed to accurately probe the relationship between nuclear and host galaxy ISM properties in a large sample of ~90 quasars at the brightest end of the AGN luminosity function (log LBol > 47.3) and at the peak of their number density (z~2.5-3.5)We will report on the discovery of highly accreting (0.3-3Ledd), ten billion solar masses SMBHs being able to produce very powerful (up to ~ 4% of L_bol) ionized outflows and accretion disk windsThe impact of AGN-driven feedback on their host galaxies will be also discussed.

The WISE/SDSS selected hyper-luminous (WISSH) quasars survey is an extensive multiband observing program (from millimeter wavelengths to hard X rays) to investigate the role of nuclear activity in SMBH-galaxy self-regulated growth via extended outflows. Our ongoing project is designed to accurately constrain both AGN and host galaxy ISM properties in a large sample of ~ 90 broad-line quasars at the brightest end of the AGN luminosity function (L_bol > 1e14 L_sun) and at the peak of their number density (z ~ 2 - 4)I will review the most relevant results obtained to date with emphasis on the discovery of extremely powerful (up to ~ 4% of L_bol) ionized outflows, the relation between AGN properties (obscuration, luminosity and Eddington ratio) and large-scale winds, and the SED of these hyper-luminous quasars.

Obscured AGN are a crucial ingredient to understand the full growth history of super massive black holes and the coevolution with their host galaxies, since they constitute the bulk of the BH accretion. In the distant Universe, many of them are hosted by submillimeter galaxies (SMGs), characterized by a high production of stars and a very fast consumption of gas. Therefore, the analysis of this class of objects is fundamental to investigate the role of the ISM in the early coevolution of galaxies and black holesWe collected a sample of six obscured X-ray selected AGN at z>2.5 in the CDF-S, detected in the far-IR/submm bands. We performed a multiwavelength analysis in order to characterize their physical properties, as well as those of their host galaxies (e.g. column density, accretion luminosity, stellar mass, SFR, dust and gas mass). I will present the results of the X-ray spectral analysis of these sources based on the 7Ms Chandra data - the deepest X-ray observation ever carried out on any field - along with their broad-band spectral energy distributions (SEDs), built up using the public UV to far-IR photometry from the CANDELS and Herschel catalogs. By comparing the column density associated with the ISM (estimated measuring the size of the system) with that obtained from the X-ray data, it is possible to understand whether the ISM in the host galaxy may be able to produce a substantial part of the observed nuclear obscuration.

The systematic exploration of hyper-luminous (log LBol > 47) quasars shining at the golden epoch of AGN activity (i.e. z~2-4) offer the opportunity of overcoming the luminosity bias in the exploration of the accretion phenomenon. The WISE All-Sky Survey allowed to spot the most luminous quasars in the universe. In this talk, we will present the results of our on-going study of the XMM/Chandra/NuSTAR observations of WISE-selected hyper-luminous quasars regardless of the amount of their obscuration (i.e. both blue and heavily reddened). We report on the correlations between the X-ray and Optical, UV and MIR properties, and on the behavior of the X-ray bolometric correction at the brightest end of the luminosity function. We find that WISE-selected hyper-luminous quasars show much lower X/Opt flux and X/MIR luminosity ratios than those of AGN typically studied so far. This “X-ray weakness” can be a key ingredient for accelerating powerful ionized outflows (pervasively detected in the UV/optical band) and, furthermore, radiation-driven winds can be effective in destroying the X-ray corona and quenching the X-ray emission.

In recent years, with the goal of understanding the large scale structure around high-z QSO, we have obtained deep r,i,z, band imaging at Large Binocular Telescope (LBT) and Y and J band at CFHT Telescope of the field around the quasar SDSSJ1030+0524 (z=6.3). I present here some results, in particular the photometric catalogue of the sources, the selection process of Lyman break galaxies in the QSO halo and the main properties of these galaxies.

We present the largest high-redshift (30 at z>3. We compute the number counts in the observed 0.5-2 keV band, finding a decline in the number of sources at z>3 and constraining phenomenological models of X-ray background. We compute the AGN space density at z>3 in two different luminosity bins. At higher luminosities (logL(2-10 keV) > 44.1 erg/s) the space density declines exponentially, dropping by a factor ~20 from z~3 to z~6. The observed decline is ~80% steeper at lower luminosities (43.55 erg/s < logL(2-10 keV) < 44.1 erg/s), from z~3 to z~4.5. We study the space density evolution dividing our sample in optically classified Type 1 and Type 2 AGN. At logL(2-10 keV) > 44.1 erg/s, unobscured and obscured objects may have different evolution with redshift, the obscured component being three times higher at z~5. Finally, we compare our space density with predictions of quasar activation merger models, whose calibration is based on optically luminous AGN. These models significantly overpredict the number of expected AGN at logL(2-10 keV) > 44.1 erg/s with respect to our data., Comment: 18 pages, 13 figures. Accepted for publication on ApJ

PG1247+267 is one of the most luminous known quasars at $z\sim2$ and is a strongly super-Eddington accreting SMBH candidate. We obtained NuSTAR data of this intriguing source in December 2014 with the aim of studying its high-energy emission, leveraging the broad band covered by the new NuSTAR and the archival XMM-Newton data. Several measurements are in agreement with the super-Eddington scenario for PG1247+267: the soft power law ($\Gamma=2.3\pm0.1$); the weak ionized Fe emission line and a hint of the presence of outflowing ionized gas surrounding the SMBH. The presence of an extreme reflection component is instead at odds with the high accretion rate proposed for this quasar. This can be explained with three different scenarios; all of them are in good agreement with the existing data, but imply very different conclusions: i) a variable primary power law observed in a low state, superimposed on a reflection component echoing a past, higher flux state; ii) a power law continuum obscured by an ionized, Compton thick, partial covering absorber; and iii) a relativistic disk reflector in a lamp-post geometry, with low coronal height and high BH spin. The first model is able to explain the high reflection component in terms of variability. The second does not require any reflection to reproduce the hard emission, while a rather low high-energy cutoff of $\sim100$ keV is detected for the first time in such a high redshift source. The third model require a face-on geometry, which may affect the SMBH mass and Eddington ratio measurements. Deeper X-ray broad-band data are required in order to distinguish between these possibilities., Comment: 12 pages, 10 figure. Accepted for publication in A&A

Star-forming galaxies are considered to be the leading candidate sources that dominate the cosmic reionization at z>7, and the search for analogs at moderate redshift showing Lyman continuum (LyC) leakage is currently a active line of research. We have observed a star-forming galaxy at z=3.2 with Hubble/WFC3 in the F336W filter, corresponding to the 730-890A rest-frame, and detect LyC emission. This galaxy is very compact and also has large Oxygen ratio [OIII]5007/[OII]3727 (>=10). No nuclear activity is revealed from optical/near-infrared spectroscopy and deep multi-band photometry (including the 6Ms X-ray, Chandra). The measured escape fraction of ionizing radiation spans the range 50-100\%, depending on the IGM attenuation. The LyC emission is detected at S/N=10 with m(F336W)=27.57+/-0.11 and it is spatially unresolved, with effective radius R_e7 allowing a direct comparison with lower redshift LyC emitters, as reported here., Comment: 6 pages, 5 figures, ApJ submitted (comments welcome)

Star-forming galaxies are considered to be the leading candidate sources that dominate the cosmic reionization at z>7, and the search for analogs at moderate redshift showing Lyman continuum (LyC) leakage is currently a active line of research. We have observed a star-forming galaxy at z=3.2 with Hubble/WFC3 in the F336W filter, corresponding to the 730-890A rest-frame, and detect LyC emission. This galaxy is very compact and also has large Oxygen ratio [OIII]5007/[OII]3727 (>=10). No nuclear activity is revealed from optical/near-infrared spectroscopy and deep multi-band photometry (including the 6Ms X-ray, Chandra). The measured escape fraction of ionizing radiation spans the range 50-100\%, depending on the IGM attenuation. The LyC emission is detected at S/N=10 with m(F336W)=27.57+/-0.11 and it is spatially unresolved, with effective radius R_e7 allowing a direct comparison with lower redshift LyC emitters, as reported here., 6 pages, 5 figures, ApJ submitted (comments welcome)

We present the discovery of a giant $\gtrsim$100~kpc Ly$��$ nebula detected in the core of the X-ray emitting cluster CL~J1449+0856 at $z=1.99$ through Keck/LRIS narrow-band imaging. This detection extends the known relation between Ly$��$ nebulae and overdense regions of the Universe to the dense core of a $5-7\times10^{13}$ M$_{\odot}$ cluster. The most plausible candidates to power the nebula are two Chandra-detected AGN host cluster members, while cooling from the X-ray phase and cosmological cold flows are disfavored primarily because of the high Ly$��$ to X-ray luminosity ratio ($L_{\mathrm{Ly��}}/L_{\mathrm{X}} \approx0.3$, $\gtrsim10-1000\times$ higher than in local cool-core clusters) and by current modeling. Given the physical conditions of the Ly$��$-emitting gas and the possible interplay with the X-ray phase, we argue that the Ly$��$ nebula would be short-lived ($\lesssim10$ Myr) if not continuously replenished with cold gas at a rate of $\gtrsim1000$ M$_{\odot}$ yr$^{-1}$. We investigate the possibility that cluster galaxies supply the required gas through outflows and we show that their total mass outflow rate matches the replenishment necessary to sustain the nebula. This scenario directly implies the extraction of energy from galaxies and its deposition in the surrounding intracluster medium, as required to explain the thermodynamic properties of local clusters. We estimate an energy injection of the order of $\thickapprox2$ keV per particle in the intracluster medium over a $2$ Gyr interval. In our baseline calculation AGN provide up to $85$% of the injected energy and 2/3 of the mass, while the rest is supplied by supernovae-driven winds., 15 pages, 11 figures, 1 appendix. Accepted for publication in ApJ