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Related papers: QSO obscuration at high redshift ($z \gtrsim 7$): …

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We present and discuss optical imaging of 76 AGN which represent the 2MASS-selected sample for z<0.3, from a full list of 243. They are found to have dust-obscured nuclei, residing in host galaxies that show a high fraction (>70%) of tidal…

Astrophysics · Physics 2009-11-07 J. B. Hutchings , N. Maddox , R. M. Cutri , B. O. Nelson

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…

Astrophysics of Galaxies · Physics 2016-07-27 Marta Volonteri , Yohan Dubois , Christophe Pichon , Julien Devriendt

Recent JWST observations have revealed a population of high-redshift galaxies ($z\gtrsim5$) exhibiting unexpectedly bright ultraviolet (UV) nitrogen emission lines. The strong N III] and N IV] features imply nitrogen-to-oxygen abundance…

Astrophysics of Galaxies · Physics 2025-12-04 Peixin Zhu , James Trussler , Lisa J. Kewley

In order to relate the observed evolution of the galaxy stellar mass function and the luminosity function of active galactic nuclei (AGN), we explore a co-evolution scenario in which AGN are associated only with the very last phases of the…

Astrophysics of Galaxies · Physics 2018-11-28 Neven Caplar , Simon J. Lilly , Benny Trakhtenbrot

We study, by means of dedicated simulations of massive black hole build-up, the possibility to constraint the existence and nature of the AGN population at z>6 with available and planned X-ray and near infrared space telescopes. We find…

Astrophysics · Physics 2008-11-26 R. Salvaterra , F. Haardt , M. Volonteri

The supermassive black holes (SMBHs) observed at the centers of all massive galaxies are believed to have grown via luminous accretion during quasar phases in the distant past. The fraction of inflowing rest mass energy emitted as light,…

Astrophysics of Galaxies · Physics 2019-10-16 Frederick B. Davies , Joseph F. Hennawi , Anna-Christina Eilers

We study the properties of black holes and their host galaxies across cosmic time in the Illustris simulation. Illustris is a large scale cosmological hydrodynamical simulation which resolves a (106.5 Mpc)^3 volume with more than 12 billion…

Astrophysics of Galaxies · Physics 2015-07-15 Debora Sijacki , Mark Vogelsberger , Shy Genel , Volker Springel , Paul Torrey , Greg Snyder , Dylan Nelson , Lars Hernquist

We present a method for generating virtual observations from smoothed-particle-hydrodynamics (SPH) simulations. This method includes stellar population synthesis models and the reprocessing of starlight by dust to produce realistic galaxy…

Astrophysics · Physics 2009-11-11 A. Cattaneo , F. Combes , S. Colombi , E. Bertin , A. -L. Melchior

We have determined the cosmological evolution of the density of AGN and of their Nh distribution as a function of the un-absorbed 2-10 keV luminosity up to redshift 4. We used the HELLAS2XMM sample combined with other published catalogs,…

We carry out a comparative analysis of the relation between the mass of supermassive black holes (BHs) and the stellar mass of their host galaxies at $0.2<z<1.7$ using well-matched observations and multiple state-of-the-art simulations…

One of the main challenges in using high redshift active galactic nuclei to study the correlations between the mass of the supermassive Black Hole (MBH) and the properties of their active host galaxies is instrumental resolution. Strong…

The origin of obscuration in Active Galactic Nuclei (AGN) is still an open debate. In particular, it is unclear what drives the relative contributions to the line-of-sight column densities from galaxy-scale and torus-linked obscuration. The…

We examine the relationship between galaxies, supermassive black holes and AGN using a sample of 22,000 narrow-emission-line AGN drawn from a a sample of 122,000 galaxies from the Sloan Digital Sky Survey. We have studied how AGN host…

Astrophysics · Physics 2009-11-10 Guinevere Kauffmann , Timothy Heckman

We present a study of the connection between black hole accretion, star formation, and galaxy morphology at z<=2.5. We focus on active galactic nuclei (AGNs) selected by their mid-IR power-law emission. By fitting optical to far-IR…

In this work we study the co-evolution of central black holes (BHs) and host galaxies by utilizing an advanced iteration of the DELPHI semi-analytical model of galaxy formation and evolution. Based on dark matter halo merger trees spanning…

Astrophysics of Galaxies · Physics 2024-03-25 Olmo Piana , Hung-Yi Pu , Kinwah Wu

(Abridged) In the last decade several massive molecular gas reservoirs were found <100 kpc distance from active galactic nuclei (AGNs), residing in gas-rich companion galaxies. The study of AGN-gas-rich companion systems opens the…

Astrophysics of Galaxies · Physics 2017-01-18 J. Fogasy , K. K. Knudsen , C. D. P. Lagos , G. Drouart , V. Gonzalez-Perez

High redshift active galactic nuclei (AGN) provide key insights into early supermassive black hole growth and cosmic evolution. This study investigates the parsec-scale properties of 86 radio-loud quasars at z $\geq$ 3 using very long…

High Energy Astrophysical Phenomena · Physics 2025-02-24 Shaoguang Guo , Tao An , Yuanqi Liu , Chuanzeng Liu , Zhijun Xu , Yulia Sotnikova , Timur Mufakharov , Ailing Wang

To understand the Active Galactic Nuclei (AGN) phenomenon and their impact on the evolution of galaxies, a complete AGN census is required; however, finding heavily obscured AGNs is observationally challenging. Here we use the deep and…

We have obtained optical imaging with the Canada France Hawaii Telescope (CFHT) of 21 2MASS-selected QSOs of redshift greater than 0.3. This paper complements the sample of lower redshift 2MASS QSOs previously published. The QSOs have…

Astrophysics · Physics 2009-11-11 J. B. Hutchings , A. Cherniawsky , ; R. M. Cutri , B. O. Nelson

Type 2 active galactic nuclei (AGN) show signatures of accretion onto a supermassive black hole through strong, high-ionization, narrow emission lines extended on scales of 100s to 1000s of parsecs, but they lack the broad emission lines…

High Energy Astrophysical Phenomena · Physics 2022-09-21 M. Lynne Saade , Murray Brightman , Daniel Stern , Matthew A. Malkan , Javier A. Garcia
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