We study the spatial distribution of X-ray selected AGN in the framework of hierarchical coevolution of supermassive black holes (BHs) and their host galaxies and dark matter (DM) haloes. To this end, we have applied the theoretical model developed by Croton et al. (2006), De Lucia & Blaizot (2007) and Marulli et al. (2008) to the output of the Millennium Run and obtained hundreds of realizatio...

In this paper, we present a new implementation of feedback due to active galactic nuclei (AGN) in cosmological simulations of galaxy formation. We assume that a fraction of jet energy, which is generated by an AGN, is transferred to the surrounding gas as thermal energy. Combining a theoretical model of mass accretion onto black holes with a multiphase description of star-forming gas, we self-c...

We explore the evolution with redshift of the rest-frame colours and space densities of active galactic nuclei (AGN) hosts (relative to normal galaxies) to shed light on the dominant mechanism that triggers accretion on to supermassive black holes as a function of cosmic time. Data from serendipitous wide-area XMM surveys of the Sloan Digital Sky Survey (SDSS) footprint (XMM/SDSS; Needles in th...

We discuss a sample of 29 AGN (16 narrow-lined and 13 broad-lined) discovered in a spectroscopic survey of ∼ 1000 star-forming Lyman-break galaxies (LBGs) at z ≃ 3. Reaching apparent magnitudes of RAB = 25.5, the sample includes broad-lined AGN approximately 100 times less UV luminous than most surveys to date covering similar redshifts, and the first statistical sample of UV/optically selected...

We cross-matched Wide-field Infrared Survey Explorer (WISE) sources brighter than 1 mJy at 12μm with the Sloan Digital Sky Survey (SDSS) galaxy spectroscopic catalog to produce a sample of ∼ 10 galaxies at 〈z〉=0.08, the largest of its kind. This sample is dominated (70%) by star-forming (SF) galaxies from the blue sequence, with total IR luminosities in the range ∼ 10 − 10L⊙. We identify which ...

We study two aspects of the differences between Active Galactic Nuclei (AGN) of the two Fanaroff-Riley types in order to investigate the causes of the F–R divide. We (a) contrast the properties of the optical cores in beamed and unbeamed AGN of the two types, incorporating Hubble Space Telescope measurements of the unbeamed objects, and (b) contrast the nuclear magnetic field geometry of the be...

The violation of the equivalence principle (VEP) causing neutrino oscillations is of current interest. We study here the possibility of not only flavor oscillation but spin flavor oscillation of ultra high energy (∼ 1 PeV) neutrinos emanating from AGN due to VEP and due to the presence of a large magnetic field (∼ 1 Tesla) in AGN. In particular we look at the resonance spin flavor conversion dr...

Aims. A complete census of obscured Active Galactic Nuclei (AGN) is necessary to reveal the history of the super massive black hole (SMBH) growth and galaxy evolution in the Universe given the complex feedback processes and the fact that much of this growth occurs in an obscured phase. In this context, hard X-ray surveys and dedicated follow-up observations represent a unique tool for selecting...

The violation of the equivalence principle (VEP) causing neutrino oscillations is of current interest. We study here the possibility of not only flavor oscillation but spin flavor oscillation of ultra high energy (∼ 1 PeV) neutrinos emanating from AGN due to VEP and due to the presence of a large magnetic field (∼ 1 Tesla) in AGN. In particular we look at the resonance spin flavor conversion dr...

The current paradigm for radio-quiet AGNs is reviewed, taking into account new results from recent large-scale surveys carried out from the ground and from space. Topics include structure of the central engine, AGN demography, fueling/triggering processes, and connection between the supermassive black hole, host galaxy, circumnuclear starburst and AGN. Dependences on AGN power and lookback time...