Search

These are the slides of Elena Pian's presentation at the Conference

Presentation of the results obtained by optical and infrared interferometry on Active Galactic Nuclei (AGN), especially from the Very Large Telescope Interferometer (VLTI). The presentation covers both continuum measurements of sizes, of radial brightness distributions and elongations, of detailed imaging studies, of variability, and of dust parallaxes, as well as spectro-interferometry of emission lines in the broad line region.

The A3391/95 clusters harbor bright central radio sources, which makes them ideal objects to probe the ICM-AGN interaction. The future JAXA/NASA/ESA mission, the X-Ray Imaging and Spectroscopy Mission (XRISM) will enable us to resolve line emission and the motion of the ICM affected by AGN feedback. Through simulation using cluster properties obtained from eROSITA and XMM-Newton, a forecast of the best observing strategy for XRISM high-resolution spectroscopy will be made. Given the complexity of the system, we will probe their merger state, as well. We further extend the central AGN-ICM study to a larger sample, namely using the first eROSITA All-Sky Survey (eRASS1) cluster sample in the EMU pilot field using the Australian ASKAP radio telescopes. We present preliminary results of the X-ray morphological properties of this sample. Athena will complete the AGN-ICM study, for instance, to investigate in great detail the chemical distribution and central cluster gas motion due to the central AGN feedback.

A schematic of the AGN and the main source of linear polarization in the optical and UV range, the scattering, both from the continuum and from the broad lines, is shown. Some examples of potential uses of linear polarimetry are presented, such as the observation of broad lines in type 2 AGNs, the measurement and structure of the BLR, a new method to measure the mass of supermassive black holes, and binary supermassive black hole models. &nbsp

Active galactic nuclei play a key role in the evolution of galaxies, but their immediate environments are poorly understood due to a lack of angular resolution. Infrared interferometry makes it possible to resolve the circumnuclear dust in the nearest Seyfert 2, the Circinus Galaxy. Previous observations have revealed complex structures and polar dust emission but interpretation was limited to Gaussian modeling. MATISSE makes it possible to image these structures for the first time. We aim to precisely map the morphology and temperature of the dust surrounding this active nucleus through interferometric imaging. We observed the Circinus Galaxy with VLTI/MATISSE, producing 150 correlated flux spectra and 100 closure phase spectra. The novel inclusion of closure phases makes interferometric imaging possible for the first time. We use IRBis to reconstruct images in the N-band at ∼10mas resolution. We fit blackbody functions with dust extinction to several aperture-extracted fluxes from the images to produce a temperature distribution of central dusty structures. We find significant substructure in the circumnuclear dust: around 0.5 Jy of central unresolved flux, a thin disk with diameter 1.9 pc oriented along ∼ 45 deg, and ∼ 4pc × 1.5 pc polar emission extending orthogonal to the disk. The polar emission exhibits patchiness, which we attribute to clumps of dust. Flux enhancements to the East and West of the disk are seen for the first time. We distinguish the temperature profiles of the disk and the polar emission: the disk shows a steep temperature gradient indicative of denser material; the polar profile is flatter, indicating clumpiness and/or lower dust density. The unresolved flux shows a high temperature, ≈ 370 K. The polar dust remains warm (∼ 200 K) out to 1.5 pc from the disk. We attribute approximately 60% of the 12 μm flux to the polar dust, 10% to the disk, and 6% is unresolved; the remaining flux is resolved out. The recovered morphology and temperature distribution resembles modeling of accretion disks with radiation-driven winds at large scales, but we place new constraints on the sub-parsec dust. The subparsec features imaged here place new, spatially resolved constraints on physical modeling of circumnuclear dust in active galaxies; we show strong evidence that the polar emission consists of dust clumps. The dynamics of the structures and their role in the Unified Model remain to be explored.

The Mid-infrared E-ELT Thermal Infrared imager and Spectrograph (METIS) is one of the three first-light instruments selected for the European Extremely Large Telescope (ELT) and will cover the thermal infrared wavelength range, from ca. 3 - 13 microns. It will be a versatile instrument featuring diffraction-limited imaging and long-slit spectroscopy in the L/M and N bands as well as high spectral resolution (R ~ 100,000) integral field spectroscopy in the L and M bands. Its spatial resolution of 25 (70) mas in the L (N) band corresponds to a linear scale of 1 (3) parsec in nearby (10 Mpc) galaxies. For nearby AGNs, METIS forms the missing link between JWST and ground-based interferometry in both resolution and sensitivity. METIS will primarily observe continuum emission from dust at 100-800 K, but it will also be sensitive to the emission lines in this wavelength range, e.g. Brackett alpha, coronal lines like [SiIX] and [ArVI] and [AlVI], molecular lines of CO and H2O, and broad silicate emission and absorption lines. As such it is well matched to tackle several of the outstanding questions in current AGN research including "What triggers AGN activity?" and "How do AGN outflows connect to the host galaxy?". In this talk, I review METIS' instrumental capabilities with a particular focus on the prospects for AGN research.

The sample of 61 isolated galaxies with AGNs was formed by cross-matching the 2MIG (2MASS Isolated Galaxy) catalogue with the Veron-Cetty catalogue of quasars and AGNs, where the restriction was used for Ks < 12.0 mag and Vr < 15 000 km/s (Pulatova et al. 2015, Karachentseva et al. 2010, Veron-Cetty+2010). These host galaxies had no merging at least 3~Gyrs, so this is could be the unique laboratory for recognizing their internal properties and physical parameters of accretion on the supermassive black holes outside of the environment. X-ray radiation of AGN commonly explained by thermal Comptonization of the soft UV/optical radiation, produced by the inner parts of accretion disk. This radiation is typically described by a power-law model and an exponential cut-off at high energies. In addition to these components in AGN`s spectrum there are the reflection components appear as "reflection hump" at ~ 20-30 keV and a Fe Kalpha near 6.4~keV. In the previous works (e.g., Vavilova et. al. 2015, Vasylenko et.al. 2020) we performed a spectral analysis of sample of several 2MIG isolated AGNs observed by the XMM-Newton, Chandra, and Swift/XRT. We found that these AGNs have smaller luminosity between 2-10 keV in comparison with the typical luminosity for the Seyfert galaxies, i.e. L2-10 keV ~ 1042 erg/s. The spectra of two sources, NGC 5347 and MCG-02-09-040, show the neutral Fe Kalpha emission line. The X-ray spectrum of NGC 5347 described by a pure reflection model with Ecut ~ 117 keV and without signs of transmitted radiation. The X-ray spectrum of MCG-02-09-040 shows the presence of heavy neutral obscuration of NH ~ 1024 cm−2. In this work we also present preliminary results of the X-ray analysis of Sy2 NGC 3081 based on the Chandra and XMM-Newton observations in the 0.5-12.0 keV energy band., {"references":["Pulatova N.G., Vavilova I.B., Sawangwit U., Babyk Iu., Klimanov S. (2015). The 2MIG isolated AGNs – I. General and multiwavelength properties of AGNs and host galaxies in the northern sky, Mon. Not. R. Astron. Soc., 447, 3, 2209–2223.","Karachentseva V.E., Mitronova S.N., Melnyk O.V. et al. (2010). Catalog of isolated galaxies selected from the 2MASS survey. Astrophys. Bull., 65, 1–17.","Véron-Cetty M.-P., Véron P. (2010). A catalogue of quasars and active nuclei: 13th edition, Astron. Astrophys., 518, id.A10.","Vavilova I.B., Vasylenko A.A., Babyk Iu.V., Pulatova N.G. (2015). X-ray spectral properties of the isolated AGNs: NGC 1050, NGC 2989, ESO 317-038, ESO 438-009. Odessa Astron. Publ., 28(2), 150-153.","Vasylenko A.A., Vavilova I.B., Pulatova N.G. (2020). Isolated AGNs NGC 5347, ESO 438-009, MCG-02-04-090, and J11366-6002: Swift and NuSTAR joined view. Astron. Nachr., 341, 8, 801-811."]}

We present an ongoing research effort to identify ionization sources in nearby AGN using Apache Point Observatory (APO) and the Hubble Space Telescope (HST). We measure emission line ratios along the spatial extents of the narrow line region (NLR) using spectra from APO's Dual Imaging Spectrograph (DIS) and HST's Space Telescope Imaging Spectrograph (STIS). The spectra reveal prominent emission lines of ionized gas that can be primarily attributed to star formation or AGN ionization. We construct BPT diagrams and compare with HST color images to isolate these regions and determine their connection to the kinematics of the outflowing gasses. When combined with our ongoing study of mass outflow rates, these efforts will help further our overall goal of determining the effectiveness of AGN feedback on their host galaxies.

In the last decade, convolutional neural networks (CNNs) have revolutionized the field of image processing and have become increasingly popular among astronomers for morphological analysis of galaxies. This push has been driven by the fact that they are the perfect alternative to the traditional techniques of obtaining morphological classifications --- expert visual classification, citizen science projects, and fitting light profiles, none of which is easily scalable to large data volumes. However, most previous applications of CNNs to morphological analysis have required a large training set of real galaxies with pre-determined classifications. However, if CNNs are to become the method of choice for analyzing unclassified data from future surveys, this necessitates an algorithm that does not require a large pre-classified training set of real galaxies from the same survey. The challenge of training a machine learning algorithm to classify brand new data, which has not been manually/previously looked at, is not unique to astronomy and is applicable to many other scientific fields which use large amounts of data such as the biomedical sciences. In this talk, I will outline how we have successfully trained a Bayesian CNN called Galaxy Morphology Network (GaMorNet) with a very small amount of real data and used it to extract morphological parameters of galaxies at a variety of redshifts from different surveys. We first trained GaMorNet on a large simulation suite of galaxies and then used a small amount of real data to perform transfer-learning/domain adaptation. We have already demonstrated that a preliminary classification-version of GaMorNet (Ghosh et. al. 2020) can be successfully applied to data from different surveys with misclassification rates of < 5%. We have also used GaMorNet to study the morphology and quenching of ~100,000$ (z~0) SDSS and ~20,000(z~1) CANDELS galaxies using morphology-separated color-mass diagrams. Using the GaMorNet classifications, we find that bulge- and disk-dominated galaxies have distinct color-mass diagrams with separate evolutionary pathways. For both datasets, disk-dominated galaxies peak in the blue cloud, across a broad range of masses, consistent with the slow exhaustion of star-forming gas. In contrast, bulge-dominated galaxies are mostly red, with much smaller numbers down toward the blue cloud, suggesting rapid quenching and fast evolution across the green valley. GaMorNet is one of the very few publicly availableCNNs in astronomy, complete with trained models. I will also outline in this talk why GaMorNet is not a black-box and how the representations learned by the network are highly amenable to visual interpretation. We have used a combination of different CNN visualization techniques to investigate and shed light on GaMorNet’s decision-making process, making our results interpretable, reproducible, and robust. &nbsp

We present a detailed study of ionized outflows in a large sample of 650 hard X-raydetected AGN. Taking advantage of the legacy value of the BAT AGN SpectroscopicSurvey (BASS, DR1), we are able to reveal the faintest wings of the [OIII] emissionlines associated with outflows. The sample allows us to derive the incidence of outflowscovering a wide range of AGN bolometric luminosity and test how the outflowparameters are related to various AGN power tracers, such as Black Hole Mass,Eddington Ratio, Luminosity. Weshow how ionized outflows are more frequentlyfound in type 1.9 and type 1 AGN with respect to the low fractionin type 2 AGN. Within such a framework, wedemonstrate how type 2 AGNoutflows are almost evenly balanced between blue- and red-shifted winds. This, instrong contrast with type 1 and type 1.9 AGN outflows which are almost exclusivelyblue-shifted. Finally, weprove how the outflow occurrence is driven by the accretionrate, whereas the dependence of outflow properties with respect to the other AGNpower tracers happens to be quite mild.

Most of what we know about active galactic nuclei (AGNs) has been driven, or at least strongly shaped, by our methods for finding them, and multiwavelength AGN surveys have achieved remarkable successes in recent decades. I will present a broad, and thus necessarily shallow, review of such multiwavelength AGN surveys. I will first present some brief introductory points on, e.g., general survey approaches, AGN luminosities, host galaxies, and anisotropic emission/obscuration. I will then review many of the key current surveys and their results, separating these into ground-based and space-based surveys. Finally, I will discuss some future prospects including essential remaining questions and "discovery space" considerations. A video presentation of this talk is available at https://www.youtube.com/watch?v=jnItH5jxmlA, A video presentation of this talk is available at https://www.youtube.com/watch?v=jnItH5jxmlA

The Nearby Magellanic Clouds system covers 180 square degrees on the sky. Much of it has been mapped across the electromagnetic spectrum at high angular resolution and sensitivity –X-ray (XMM-Newton), UV (UVIT), optical (SMASH), IR (VISTA, WISE, Spitzer, Herschel), radio (ATCA, ASKAP, MeerKAT). This provides us with an excellent dataset to explore the galaxy populations behind the stellar-rich Magellanic Clouds. We seek to identify and characterise AGN via machine learning algorithms on this exquisite data set. Our project focusses not on establishing sequences and distributions of common types of galaxies and active galactic nuclei (AGN), but seeks to identify extreme examples, building on the recent accidental discoveries of unique AGN.

Quasars at z>6 (age of the Universe: 100 Msun/yr, and, despite the young cosmic age, they appear chemically enriched. These humongous star formation and accretion rates are fueled by immense gaseous reservoirs. Here we review how to the quasar redshift frontier has been pushed forward. We discuss the lessons learned on the formation and early growth of massive black holes, on their host galaxies, their environment, and on the intergalactic medium at the end of reionization. In particular, we demonstrate how observations at (sub-)mm wavelengths can shed light, for the first time, on the mass, spatial extent, chemistry, kinematics, and physical properties of the interstellar medium in these quasars, thus constraining the build up of the first massive galaxies and black holes and the AGN impact on their gas, and testing the interstellar medium properties in regimes that are not observable anywhere else in the universe.

A rich phenomenology of jets, winds, and accretion states has been observed in both active galactic nuclei (AGN) and X-ray binaries (XRBs), suggesting a connection between the accretion and ejection flows at different black hole masses, from supermassive down to stellar mass.The X-ray emission, associated with the accretion flow,is strongly coupled with the radio emission,associated with a jet. Strong correlations between the radio and the X-rayluminosities are found in XRBs, as well as in radio-loud and radio-quiet AGN. I will review observational evidences in favour of the disc-jet coupling at different luminosities and accretion rate scales in AGN and compare this phenomenology with XRBs. The co-existence of jets and winds in AGN will be also discussed in comparison with XRBs. The results will be discussed within the current accretion-ejection physical scenarios.

Galaxy formation theories struggle to explain the role of Black Hole accretion in shaping galaxies over cosmic time. Radio feedback, associated to radio jets, is accepted as a fundamental component of the lifecycle of the most massive radio loud early-type galaxies (Radio Loud ETGs, i.e. Radio Galaxies, RGs), at least in the late stages of cosmic evolution (z < 1). The many details of such process, however, still remain poorly understood. It is generally accepted that High Excitation Radio Galaxies (HERGs) are triggered by cold gas transported to the center through merging or collisions with gas-rich galaxies, while accretion in Low Excitation Radio Galaxies (LERGs) may occur directly from the hot phase of the IGM. The most compelling evidence that cold gas can play a role in fuelling LERGs as well, is that in such systems dust and molecular gas are detected in larger quantities than in radio-quiet ETGs. The origin of this gas (external or secular) remains still unclear. Systematic high-resolution CO imaging of radio galaxies (in which radio jets are currently active) together with kinematic information on the stellar and ionized gas components, is fundamental to isolate the role played by radio-mode feedback in the overall formation and evolution of ETGs, allowing also to do a crucial comparison with existing studies of radio-quiet ETGs (e.g. ATLAS3D sample). For this purpose, we have selected a complete volume-limited sample of eleven nearby (z < 0.03) RGs associated with elliptical galaxies, selected from the Ekers et al. (1989) parent sample of 90 radio galaxies in the Southern sky. All the selected galaxies have low-power (P1.4GHz ≤ 1025 W Hz−1), low accretion rate, and FRI type or (arcsec-scale) compact radio morphology. For all the sources, we have already acquired a set of multi-wavelength data, spanning from the radio to the mm regime. Here we present the results obtained so far by analyzing ALMA Cycle 3 CO(2-1) observations of 9 targets, with resolutions of few hundreds of parsecs at the source redshifts. The CO(2-1) line emission was detected in 6 out of 9 targets (detection significance from 8 to 45 sigma; 66% detection rate). CO(2-1) maps show rotating disc structures in all the sources, with some peculiar cases in which the gas disk shows a disturbed morphology that seems to suggest an interaction with the radio jets. The detected CO discs are mostly located in the inner kpc-sub-kpc scales of the host galaxy. Available optical images were used to investigate the relative distribution of gas and dust: they result mostly co-spatial, with dust extending on larger scales in some cases. The study of the CO kinematics is still ongoing, but preliminary results show hints of the presence of of non-circular motions (i.e. inflow/outflow) in at least one of the detected CO discs.&nbsp

The primary emission in Actve Galactic Nuclei (AGN) is widely believed to be due to Comptonisation of the thermal radiation from the accretion disk in a "corona" of hot electrons. The resulting spectra can, in the firstapproximation, be modelled with a cutoff power law.Taking advantage of MoCA, a Monte Carlo code calculating spectral and polarization properties of the coronal emission, we computed Comptonization spectra for differentparameters of the hot corona, comparing them with cutoff power laws. Plots to convert phenomenologicalparameters (cutoff energy and photon index) into physical ones (temperature and optical depth) will be presentedand discussed.

Virial–based methods for estimating active supermassive black hole masses are commonly used on extremely large spectroscopic quasar catalogs. Most spectral analyses, though, do not pay enough attention to the detailed continuum decomposition. To understand how this affects virial mass estimates, I tested the influence of host galaxy light on them by means of a detailed spectral analysis with the new software QSFit. I will present that taking or not the host galaxy component into consideration influences the emission line fitting. This can significantly affect the viral mass estimates, especially at low redshift, where in fact dimmer quasars and more visible host galaxies are observed.

Numerous models and simulations expect that AGN should have a negative feedback effect on star formation in their host galaxy, by generating outflows and by injecting energy into the ISM and in their circugalactic medium. Recent models predict that AGNs may also have a positive feedback effect by enhancing star formation in some regions of their host galaxies. I will quickly review these models and then mostly focus on the observational evidence (or lack thereof) of such feedback effects, thorugh different observational diagnostics, in different classes of AGNs, both locally and in the early universe.

IBISCO is a new multi-dimensional study of AGN scaling relations in a complete unbiased sample of local AGN, carried-on with IRAM, ALMA and INTEGRAL. For the first time we have included the information on the molecular gas reservoirs into the scaling relations between AGN and host galaxy properties. I will discuss scaling relations for the local sample IBISCO, and for samples from the SUPER survey and from SDSS out to z~2.

In the past 50 years, astronomers have used X-ray surveys to tackle fundamental questions for structure formation such as: How did supermassive black holes form and grow in the nuclei of galaxies? Why are their physical properties today so tightly linked to those of their hosts? What was the impact on the surrounding structures of the copious energy release, either in radiative or mechanical form, associated to the growth of such black holes in active galactic nuclei (AGN)? I will show how state of the art observations with multi-wavelength surveys have been used to give at least partial answers to some of these questions, and discuss the current knowledge of the history of black hole accretion. The next generation of wide-area, sensitive X-ray surveys designed to map the hot and energetic Universe will be heralded by eROSITA (extended ROentgen Survey with an Imaging Telescope Array), the core instrument on the Russian-German Spektrum-Roentgen-Gamma (SRG) mission, scheduled for launch in 2019. eROSITA will perform a deep survey of the entire X-ray sky, and will be about 30 times more sensitive than ROSAT in the soft energy band (0.5-2 keV), while in the hard band (2-8 keV) it will provide the first ever true imaging survey of the full sky. eROSITA is expected to yield a sample of around 3 million active galactic nuclei, which is bound to revolutionize our view of the evolution of supermassive black holes and their impact on the process of structure formation in the Universe.

The origin of the tight correlations observed between the masses of supermassive black holes (SMBHs) and host galaxy properties is still debated. Negative feedback from AGN can provide a viable explanation for these correlations. According to the theoretical models, the ejective feedback resulting from radiatively-efficient episodes of gas accretion onto SMBHs may be the main responsible for the rapid shut-off of star formation and black hole growth in the early stages of the evolution of present-day massive galaxies, which must have taken place at z>2. Here we present near-IR (SINFONI) and millimetre (ALMA) observations of z~2.5 luminous (Lbol>1e47 Lsun) quasars showing fast and extended ionised outflows. These AGN-driven outflows appear to be able to expel a large fraction of molecular and ionised gas and suppress star formation in the outflow region. However, the detection of Halpha emission along the edges of the outflow cone indicates on-going star formation rates of at least 50 Msun/yr, suggesting either that AGN feedback does not affect the whole galaxy or that many feedback episodes are required before star formation is completely quenched. On the other hand, the detection also lead to a positive feedback interpretation: the AGN-driven outflow compress the surrounding gas inducing star formation. Our results highlight the possible double role of galaxy-wide outflows in host galaxy evolution. This is also supported by recent observations in the local Universe indicate that massive galactic outflows may ignite star formation within the outflow itself. We also present new ALMA observations of a sample of quasars at z∼6 optimised to investigate the extended emission associated with outflows as traced by the [CII]158μm line. Although strong and powerful AGN-driven outflows are expected at these redshifts, our analysis suggests that such outflows may not be as effective as expected in removing gas out of their host galaxies.

Blazars are a particular class of active galactic nuclei with their relativistic jets pointing close to the line ofsight of the observer. Their spectral energy distributions are dominated by non-thermal emission from the jet,consisting of two main bumps. For the so-called extreme blazars, these components each peak in the X-rayand GeV-TeV bands. Recent observations have revealed that in a few of these objects, the energy of the second peak exceedsseveral TeV (e.g. 1ES 0229+200). These intriguing objects have been suggested as sources of hadronic gamma-ray emission as well as high-energy neutrinos. Their hard TeV spectra are also valuable for indirectly probingthe extragalactic background light and the intergalactic magnetic field. In this contribution, we present the results of our observing campaign on ten promising targets performedin very-high-energygamma rays with the MAGIC telescopes. Modelling of their broadband spectra is alsodiscussed. Furthermore, we propose new targets for current and future TeV gamma-ray telescopes, selectedon the basis of hard X-ray and GeV gamma-ray emission.

The first SMBHs and their host galaxies represent some of the most extreme astrophysical objects that we currently know at z > 6. Their observed propertiesallow to constrain possible evolutionary models. Here we present some recent resultson the nature of their black hole seeds, on their mass growth rate, and on the assembly history of their host galaxies.

The majestic discovery of the first source of high frequency gravitational waves, GW150914, and of four companion sources by the LIGO and Virgo Collaboration herald the birth of a new era of exploration of the Universe. In this context, I review on our current understanding on the formation of stellar black holes, and their impact on fondamental physics. I then move into the low frequency gravitational wave domain and describe the prospective sources for LISA, the space mission that will uncover for the first time massive coalescing binary black holes. LISA will tell us about the formation of massive black holes from seeds and how they later evolve in concordance with the assembly of galactic structures. There is a close link between the high and low frequency gravitational wave universe that I will describe in my closing remarks.

The Shakura & Sunyaev model is the mostly adopted description of the thermal emission produced by the accretion disk around a black hole and infers rough estimates of the disk luminosity and the black hole mass. More advanced models have been developed in order to account for general relativistic effects, including the role of the black hole spin. My aim is to describe and compare two relativistic disk models, KERRBB and SLIMBH, to show: i) their effect on the fitting process of the Spectral Energy Distribution, and ii) the possible usage to shed light on the geometry of the dusty torus surrounding the AGN central engine

Active Galactic Nuclei (AGNs) are one of the most studied classes of objects at energies above tens of GeV with current Cherenkov Telescopes and will be a major topic for the upcoming Cherenkov Telescope Array (CTA), the next-generation ground-based gamma-ray observatory. The CTA full array, distributed over two sites, one in the northern and one in the southern hemisphere, will provide whole-sky coverage and will improve the sensitivity with respect to the current Imaging Air Cherenkov Telescope (IACTs) by a factor of five to twenty, depending on the energy. In particular, we focus our studies on three main classes: extreme BL Lacs as the possible source of Ultra-High Energy Cosmics Rays (UHECR) beams and probes of exotic physics, Narrow Line Seyfert 1 (NLS1) and AGN-driven winds as sources of very-high energies (above tens of GeV) gamma rays. In all cases we discuss the scientific relevance and we show dedicated simulations to assess the feasibility of these observations with CTA.

Gas outflowing from the AGN power source is most likely responsible of the complex interplay between the nuclear engine and the host galaxy properties, which is commonly referred to asfeedback.Winds propagating at Galactic scales represent a crucial diagnostic of AGN feedback. Both numerical simulations and observations have shown that the nature of outflows in AGN is multiphase, and that each gas phase embeds a fundamental piece of information on the driving mechanism and on the effect on the host galaxy. I will review the progresses obtained in the past 2 years to shed light on the presence of AGN/Quasar winds, on the characterisation of their physical properties, and on the multi-phase and multi-scale nature of such phenomena.&nbsp

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.

Reverberation mapping and scaling relationships based on reverberation results provide the underpinning of all estimates of quasar black hole masses. When applying these scaling relationships, there are potential pitfalls that are widely unappreciated and can result in biases that can, in turn, lead to systematic errors in the black hole mass function and therefore conclusions about the evolution of black holes over time. Potential sources of biases are discussed and it is shown how they can be mitigated.

The existence of a long-lasting link between the central black hole mass and various physical properties of their host spheroids is now a matter of fact. Studying the correlations between the two at different ages is then the best way to rebuild their cosmic evolution. Within this scenario, we have built up two complementary AGN samples able to probe the accreting phases at both a) very high luminosity (>1047 erg/s) and BH masses (109-10 Msol), i.e. the WISSH Sample, and b) very low luminosities (~1043 erg/s) and BH masses (~105 Msol), i.e. studying sources extracted from the SWIFT/BAT catalog. By performing AGN-dedicated SED-fitting procedures we derived the main physical properties of both the nuclear engine and the host galaxy of these sources, i.e. bolometric luminosities, star formation rates and stellar masses. We will present the accreting and star formation properties of these sources, comparing the two classes of objects. Moreover, we are able to constrain the BH-galaxy scaling relation over three orders of magnitudes in mass and to follow its evolution from z~3 to z~0. I will show that while the more massive galaxies populate the typical region of the already observed MBH-Mstar relation, the less massive ones are still on their way to reach the MBH-Mstar locus, especially obscured AGN which seem to be hosted in less massive galaxies compared to unobscured ones, given the same BH. We will also present a new bolometric correction, separately for AGN2 and AGN1, which spans five orders of luminosity thus allowing to derive more accurate predictions on the accretion history of the AGN and their host galaxies.

An accreting super massive black hole lurks at the center of AGNs and QSOs. Measuring its mass is not trivial due to the very small size of the sphere of influence, and the high luminosity of the AGN itself when compared to the stars in the host galaxy. I will review the currently available methods to measure the black hole mass of Type 1 AGNs (reverberation mapping, virial methods, empirical relations, accretion disk fitting), and compare their results and reliability.

The Fermi-LAT revealed that blazars dominate the census of the gamma-ray sky, and a significant correlation was found between radio and gamma-ray emission in the 0.1-100 GeV energy range. However, the possible connection between radio and very high energy (VHE, E>0.1 TeV) emission still remains elusive, owing to the lack of a homogeneous VHE sky coverage.With this work we aim to quantify and assess the significance of a possible connection between the radio emission on parsec scale measured by the very long baseline interferometry and GeV-TeV gamma-ray emission in blazars, which is a central issue for understanding the blazar physics. We use two large and unbiased AGN samples extracted from the 1FHL and 2FHL catalogs, and for comparison, we perform the same analysis by using the 3FGL 0.1-300 GeV gamma-ray energy flux.Overall, the radio and gamma-ray emission above 10 GeV turns out to be uncorrelated for all the blazar sub-classes with the exception of high synchrotron peaked objects. Conversely, when 0.1-300 GeV gamma-ray energies are considered, a strong and significant correlation is found for all of the blazar sub-classes. We interpret these results within the context of the blazar spectral energy distribution properties.

The recent detection of gravitational waves together with the discovery, few years ago, of an extraterrestrial component of high-energy neutrinos, inaugurate the era of multimessanger astrophysics. The relativistic effects owing to the beaming of the jet, that is pointing at us, make blazars the most energetic, persistent particle accelerators of the Universe. Recent observations show the evidence for a possible positional correlation between the neutrino directions detected by IceCube and the position of a flaring BL Lac object (the case of TXS0506+056). Based on a simple theoretically-motivated framework, we postulated a direct proportionality between high-energy gamma-ray and neutrino fluxes from BL Lac objects. The non-detection of high-energy neutrinos associated to Mkn421, and more in general to the most brightest gamma-ray BL Lacs, leads us to investigate on the photons target density involved in the neutrino production. We discuss a scenario that explain the neutrino emission from TXS disfavouring the brightest gamma-ray sources.&nbsp

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.

Radio galaxies (RGs) are among the most energetic manifestation of the AGN phenomenon and, as such, are extraordinarily relevant to address important unknowns relating accretion and ejection, and to investigate the role of the surrounding environment in shaping the radio morphology. The best candidates for this pioneering study are the RGs classified as FRII-LERGs, since they show both a radio morphology typical of powerful RGs (expected to have a standard accretion disc) and have an inefficient engine, as suggested by their optical spectra. In this work we study the X-ray properties of all the FRII-LERGs of the 3CR sample at z

A tight non-linear relation between the X-ray and the optical-ultraviolet luminosity has been observed in AGN over 5 orders of magnitude and up to high redshift. This suggests a coupling between the disk, emitting the primary radiation in the UV band, and the hot corona emitting in the X-ray. In this work, we have studied the Lx-Luv relation for a sample of high-redshift (z>4) quasars, selected on the basis of their spectral properties and the quality of the available observations in both X-ray and optical/UV bands. The relation shows no-evidence of evolution with redshift, which indicates a universal physical mechanism regulating the energy transfer process in the inner regions, and the observed dispersion is lower than in previous estimates. The non-linearity of the relation provides a new, powerful way to estimate the absolute luminosity, turning quasars into a new class of standard candles that can provide an important contribution in the determination of the cosmological parameters, probing cosmological time not achievable with other observational methods.

In this talk we will present results from the MAGNA (Multiple AGN Activity) project focused on the detection and study of multiple supermassive black hole systems. We investigate the physical properties (accretion rate and local environment) of multiple AGN candidates in interacting systems with respect to isolated sources with the goal to understand the mechanisms that trigger AGN activity in different stages of galaxy mergers. We report on an optical and X-ray study of an optically selected sample of four dual AGN systems at projected separations of 30–60 kpc. We compare the absorption properties in our dual AGN with those in larger samples observed in X-rays but selected in different ways (optical, IR and hard X-rays). We find that the obscured (NH~1022 cm-2) AGN fraction within the larger sample is 84\pm4 per cent (accounting for the 90 per cent error on the NH measure) up to large pair separations (100 kpc). i.e. statistically higher with respect to the fraction of obscured AGN in isolated galaxies found in X-ray surveys. This evidence is in agreement with the hypothesis that galaxy encounters are effective in driving gas inflow toward the nuclear region, thus increasing the obscuration. The talk will reflect on broader implications of these findings and will present future perspective.

AGN outflows are believed to play a major role in shaping the properties of host galaxies, by sweeping away the gas and quenching star formation (negative feedback). In this framework our MAGNUM survey aims at investigating in detail the interplay between AGN activity and star formation processes in nearby active galaxies which, due to their vicinity, are the ideal laboratories to carry out such a study. The sample comprises ten famous nearby Seyfert galaxies so far, such as Circinus, NGC 1365 and NGC 4945. Thanks to its unique combination of large field of view and spectral coverage, MUSE at VLT allowed us to map the ionised gas down to ~10 pc in several nebular emission lines revealing ubiquitous kpc-scale outflows, whose properties (e.g. velocity, mass outflow rate, kinetic rate etc...) as a function of distance from the active nucleus were measured. By matching MUSE with Chandra X-ray observations we studied the ionized gas and the outflow kinematics and energetics in its different phases and spatial scales in NGC 1365, and obtained unique insights on the properties of the outflows and of the ISM.Additionally, we recently found evidence of a new mode of star formation, occurring within a starburst outflow itself, as predicted by recent models.

After a brief overview on mass measurements and their uncertainties, I will review the relations between black hole masses and the properties of their host galaxies, focussing on their physical origin and on the implications for the models of black hole and galaxy formation. I will then present the evidences for a redshift evolution of the local relations, discussing the reliability of existing measurements and future prospects.

We report the first results of the MURALES survey, a complete program of MUSE observations of nearby (z

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.

The spectral energy distribution (SED) of quasars in UV-opticalrange is characterised by the Big Blue Bump with a pick around 1000-1300Å, broad emission lines, broad absorption lines (in ~15% of objects)and the flux decrement redward of 1215 Å caused by absorption in theintergalactic medium. Quasar UV-optical SEDs are remarkably similar fromone object to another, the main differences are in spectral index andequivalent width of emission lines. Continuum and emission lines arebelieved to originate from the hot accretion disc and circumnuclear fastmoving clumps, correspondingly. The proximity of these regions isconsidered to be the most promising explanation of the Baldwin effect: the inverse correlation of equivalent width of some emission lines with themonochromatic luminosities at UV region. On the other hand, the physicalexplanation of the difference in spectral indices and their dependence onquasar parameters are still not clear. We present the analysis of quasaremission lines properties within the wavelength range 1215-1450 Å andtheir dependence on quasar luminosity and spectral index. For this purposea set of composite spectra is compiled from subsamples of SDSS DR7 mediumresolution quasar spectra with similar spectral index at this wavelengthrange and similar monochromatic luminosities at 1450 Å. We consider thespectral index range of -2.3...-0.7, the monochromatic luminosities range of42.2...43.4, and emission features around Lyalpha+N V+Si II, O I+Si II, CII and Si IV+O IV. It is found a dependence of the emission lineequivalent width on spectral index (correlation or anti correlation) forseveral lines, mostly for those lines for which the Baldwin effect (thedecreasing of equivalent width with increasing of luminosity) wasdetected. Also we calculated virial mass of the central supermassive blackhole for composite spectra and 3535 individual quasar (using the C IVemission line) and explored dependence on quasar luminosity and spectral index. It is found, that quasar luminosity increases with increase ofblack hole's mass. But on the other hand, virial mass of the black holedoesn't depend on spectral index.

I will present the first data release of high resolution 1.5 GHz radio observations of 103 nearby galaxies with the eMERLIN array, part of the LeMMINGs survey. The sample consists of active and non-active galaxies, taken from the Palomar sample. The radio images reveal a broad variety of morphologies: one/two-sided jets, double-lobed jets, complex str uctures and star formation regions on a typical scale of ~100 pc, down to a radio luminosity of 1032erg/s. The most important result is the detection of pc-scale jetted structures associated with black hole masses down to 10$^6$ solar mass. By dividing the sample into optical classes, LINERs show more core-brightened radio morphologies and appear to be the scaled-down version of FRI radio galaxies; Seyferts show less collimated jets than LINERs. I will also present new Chandra X-ray data for the sample. I will show how the sample spreads in the X-ray/radio diagram and how the different optical classes can be interpreted based on different disc-jet models. In addition, I also find that that jetted radio sources follow the optical fundamental plane of black hole activity, suggesting a common disc-jet relationship.

On 2017 May 15, the FERMI/LAT gamma-ray telescope observed a transient source not present in any previous high-energy catalog: J1544-0649. It was visible for two consecutive weeks, with a flux peak on May 21. Subsequently observed by a Swift/XRT follow-up starting on May 26, the X-ray counterpart position was coincident with the optical transient ASASSN-17gs = AT2017egv, detected on May 25, with a potential host galaxy at z = 0.171. We conducted a 4-month follow-up in radio (Effelsberg-100 m) and optical (San Pedro Mártir, 2.1 m) bands, in order to build the overall Spectral Energy Distribution (SED) of this object. The radio data from 5 to 15 GHz confirmed the flat spectrum of the source, favoring a line of sight close to the jet axis, not showing significant variability in the explored post-burst time window. The Rx ratio, a common indicator of radio loudness, gives a value at the border between the radio-loud and radio-quiet active galactic nuclei (AGNs) populations. The CaIIH&K break value (0.29 ± 0.05) is compatible with the range expected for the long-sought intermediate population between BL Lacs and FRI radio galaxies. An overall SED fitting from the radio to gamma-ray band shows properties typical of a low-power BL Lac. As a whole, these results suggest that this transient could be a new example of the recently discovered class of radio-weak BL Lac, showing for the first time a flare in the gamma/X-ray bands.

We present the results of a systematic X-ray analysis of a complete and well-defined sample of 23 high-z (z=4-5.5) blazar candidates selected from the CLASS radio survey. In particular, we have complemented the existing archival data (mostly Chandra) with dedicated Swift-XRT observations reaching an almost complete X-ray coverage of the sample. Our aim is to the determination of the nature of all the objects in the sample using X-ray data, since a strong and flat (Gamma

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.

The August 2014 NuSTAR observation of the Seyfert 2 galaxy NGC 1068 allowed us to discover a hard X-ray flux excess with respect to observations performed 20 months earlier and 6 months later. This variability was ascribed to an unveiling event during which Compton-thick material moved temporarily out of our line of sight enabling us to unveil the direct nuclear radiation of this buried AGN. In this talk, I will discuss the results of the latest NuSTAR monitoring campaign performed between July 2017 and February 2018 with the aim of searching for flux and spectral variability on shorter time-scales (from one up to six months) and providing some tighter constraints on the number of clouds of the circumnuclear absorbing Compton-thick material, their physical properties and their distance from the illuminating source. &nbsp

Cross-correlating the INTEGRAL/IBIS - Swift/BAT AGN population with radio catalogs (NVSS, FIRST, SUMSS), we found that 25% of extended radio sources are Giant Radio Galaxes (GRG), i.e. the largest individual objects in the Universe. This fraction is four time more abundant than what found in previous studies. In 2014, we observed a pilot sample of these soft-gamma ray selected GRG at low radio frequencies with the GMRT, with the aim of studying the morphological and spectral properties of these objects. Thanks to these data, we discovered the second X-shaped GRG to date, and a previously unidentified radio galaxy. Another object, observed both at kpc and pc scales (VLBI), showed an extreme jet re-orientation (about 90 degrees). Moreover, the majority of these objects show signs of restarting activity from previous observations in the literature. Given these intriguing premises, we embarked on a radio observing campaign, using both single dish (Effelsberg) and interferometers (VLBA), to probe the lifecycle of these soft gamma-ray selected GRG. The results of this campaign will be presented, that potentially shed light on the origin and evolution of the radio phase for this extreme class of objects (and radio-loud AGN in general), and the connection with high-energy emission. The X-ray properties, and in particular the correlation between the X-ray luminosity of the AGN and the radio luminosity of both the core and the lobes, will be discussed as well.

We present a comparison between the optical and Gamma-ray light curves of the Low Frequency Peaked BL Lac object S5 1803+784 since the beginning of the Fermi-LAT mission (August 2008) up to September 2018. We also considered X-ray data from SWIFT-XRT taken in several pointings between 2009 and 2015, two of them during the 2015 flare. Furthermore we compared a VLBA radio map obtained by us in 2016 with the last available MOJAVE map (November 2012). An optical spectrum was taken during the 2015 flare. The good temporal correlation between optical and Gamma-ray fluxes supports a common origin for the emitting processes in the two energy bands. The smaller variability of the X-ray flux is consistent with an SSC scenario. The MgII 2800 A emission line is not detected during the flare, indicating that the BLR was not involved. The VLBA map suggests that a radio-emitting blob has been formed after the Gamma-ray flare and is moving along the jet.