Related papers: Supermassive Black Holes in Deep Multiwavelength S…
A supermassive black hole has been found at the centre of nearly every galaxy observed with sufficient sensitivity. The masses of these black holes are observed to increase with either the total mass or the mean (random) velocity of the…
Mergers of galaxies are thought to cause significant gas inflows to the inner parsecs, which can activate rapid accretion onto supermassive black holes (SMBHs), giving rise to Active Galactic Nuclei (AGN). During a significant fraction of…
Population synthesis models of actively accreting super-massive black holes (or active galactic nuclei -- AGN) predict a large fraction that must grow behind dense, obscuring screens of gas and dust. Deep X-ray surveys are thought to have…
Statistical studies of X-ray selected Active Galactic Nuclei (AGN) indicate that the fraction of obscured AGN increases with increasing redshift, and the results suggest that a significant part of the accretion growth occurs behind…
Active galactic nuclei (AGN) play a crucial role in galaxy evolution by influencing the observational properties of their host galaxies. We investigate the host galaxy properties of X-ray selected AGNs, focusing on differences between…
The diffuse cosmic X-ray background (CXB) is the sum of the emission of discrete sources, mostly massive black-holes accreting matter in active galactic nuclei (AGN). The CXB spectrum differs from the integration of the spectra of…
Obscured active galactic nuclei (AGN) are often invoked to explain the rapid emergence of young quasars at high redshift and are crucial for building a complete census of AGN activity and black hole growth. The advent of the James Webb…
Large extragalactic surveys allow us to trace, in a statistical sense, how supermassive black holes, their host galaxies, and their dark matter halos evolve together over cosmic time, and so explore the consequences of AGN feedback on…
We present the first quantified, statistical map of broad-line active galactic nucleus (AGN) frequency with host galaxy color and stellar mass in nearby (0.01 < z < 0.11) galaxies. Aperture photometry and z-band concentration measurements…
We present the rest-frame optical morphologies of active galactic nucleus (AGN) host galaxies at 1.5<z<3, using near-infrared imaging from the Hubble Space Telescope Wide Field Camera 3, the first such study of AGN host galaxies at these…
Today, almost every galaxy spheroid contains a massive black hole: a remnant of, and testament to, a period in its evolution when it contained an active galactic nucleus (AGN). However, the sequence and timescales of the formation of the…
Active galactic nuclei (AGN) produce the highest intrinsic luminosities in the Universe from within a compact region. The central engine is thought to be powered by accretion onto a supermassive black hole. A fraction of this huge release…
While theory and simulations indicate that galaxy mergers play an important role in the cosmological evolution of accreting black holes and their host galaxies, samples of Active Galactic Nuclei (AGN) in galaxies at close separations are…
Powerful radio galaxies at high redshift are highly useful in studies of early evolution of AGN-hosting galaxies because their observed optical and near infrared light are dominated by their stellar population rather than the nonthermal…
Our current understanding of the evolution of obscured accretion onto supermassive black holes is reviewed. We consider the literature results on the relation between the fraction of moderately obscured, Compton-thin AGN and redshift, and…
We investigate the infrared contribution from supermassive black hole activity versus host galaxy emission in the mid to far-infrared (IR) spectrum for a large sample of X-ray bright active galactic nuclei (AGN) residing in dusty,…
We present the results of a combined galaxy population analysis for the host galaxies of active galactic nuclei (AGN) identified at 0 < z < 1.4 within the SDSS, Bootes and DEEP2 surveys. We identified AGN in a uniform and unbiased manner at…
Understanding the relative roles of large-scale environment and internal host-galaxy processes in shaping AGN activity is essential for constraining models of black-hole growth and galaxy evolution. We investigate how the environment of…
The large-scale environments of active galactic nuclei (AGN) reveal important information on the growth and evolution of supermassive black holes (SMBHs). Previous AGN clustering measurements using 2-point correlation functions have hinted…
Heavily obscured accretion is believed to represent an important stage in the growth of supermassive black holes, and to play an important role in shaping the observed spectrum of the Cosmic X-ray Background (CXB). Hard X-ray (E$>$10 keV)…