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We study a sample of Herschel-PACS selected galaxies within the GOODS-South and the COSMOS fields in the framework of the PACS Evolutionary Probe (PEP) project. Starting from the rich multi-wavelength photometric data-sets available in both fields, we perform a broad-band Spectral Energy Distribution (SED) decomposition to disentangle the possible active galactic nucleus (AGN) contribution from that related to the host galaxy. We find that 37 per cent of the Herschel-selected sample shows signatures of nuclear activity at the 99 per cent confidence level. The probability to reveal AGN activity increases for bright ($L_{rm 1-1000} > 10^{11} rm L_{odot}$) star-forming galaxies at $z>0.3$, becoming about 80 per cent for the brightest ($L_{rm 1-1000} > 10^{12} rm L_{odot}$) infrared (IR) galaxies at $z geq 1$. Finally, we reconstruct the AGN bolometric luminosity function and the super-massive black hole growth rate across cosmic time up to $z sim 3$ from a Far-Infrared (FIR) perspective. This work shows general agreement with most of the panchromatic estimates from the literature, with the global black hole growth peaking at $z sim 2$ and reproducing the observed local black hole mass density with consistent values of the radiative efficiency $epsilon_{rm rad}$ ($sim$0.07).
We investigate the abundance of Super-Massive Black Hole (SMBH) seeds in primordial galaxy halos. We explore the assumption that dark matter halos outgrowing a critical halo mass M_c have some probability p of having spawned a SMBH seed. Current obse
The hierarchical galaxy formation picture suggests that super massive black holes (MBHs) observed in galactic nuclei today have grown from coalescence of massive black hole binaries (MBHB) after galaxy merging. Once the components of a MBHB become gr
We discuss the central role played by X-ray studies to reconstruct the past history of formation and evolution of supermassive Black Holes (BHs), and the role they played in shaping the properties of their host galaxies. We shortly review the progres
We addressed the so far unexplored issue of outflows induced by exponentially growing power sources, focusing on early supermassive black holes (BHs). We assumed that these objects grow to $10^9;M_{odot}$ by z=6 by Eddington-limited accretion and con
We analyse the demographics of black holes (BHs) in the large-volume cosmological hydrodynamical simulation Horizon-AGN. This simulation statistically models how much gas is accreted onto BHs, traces the energy deposited into their environment and, c