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Related papers: A simple model for quasar density evolution

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We investigate clustering properties of quasars using a new version of our semi-analytic model of galaxy and quasar formation with state-of-the-art cosmological N-body simulations. In this study, we assume that a major merger of galaxies…

Astrophysics of Galaxies · Physics 2015-12-03 Taira Oogi , Motohiro Enoki , Tomoaki Ishiyama , Masakazu A. R. Kobayashi , Ryu Makiya , Masahiro Nagashima

The molecular gas serves as a key probe of the complex interplay between black hole accretion and star formation in the host galaxies of active galactic nuclei (AGNs). We use CO(2-1) observations from a new ALMA survey, in conjunction with…

Astrophysics of Galaxies · Physics 2020-08-26 Jinyi Shangguan , Luis C. Ho , Franz E. Bauer , Ran Wang , Ezequiel Treister

Mergers of spinning black holes can give recoil velocities from gravitational radiation up to several thousand km/s. A recoiling supermassive black hole in an AGN can retain the inner part of its accretion disk, providing fuel for…

Astrophysics · Physics 2007-07-25 G. A. Shields , E. W. Bonning , S. Salviander

I review accretion and outflow in active galactic nuclei. Accretion appears to occur in a series of very small--scale, chaotic events, whose gas flows have no correlation with the large--scale structure of the galaxy or with each other. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Andrew King

We discuss constraints on the assembly history of supermassive black holes from the observed remnant black holes in nearby galaxies and from the emission caused by accretion onto these black holes. We also summarize the results of a…

Astrophysics · Physics 2007-05-23 Martin G. Haehnelt , Guinevere Kauffmann

We use zoom simulations to show how merger-driven disruption of the gas disc in a galaxy provides its central active galactic nucleus (AGN) with fuel to drive outflows that entrain and expel a significant fraction of the circumgalactic…

Astrophysics of Galaxies · Physics 2022-06-29 Jonathan J. Davies , Andrew Pontzen , Robert A. Crain

We build an evolution model of the central black hole that depends on the processes of gas accretion, the capture of stars, mergers as well as electromagnetic torque. In case of gas accretion in the presence of cooling sources, the flow is…

High Energy Astrophysical Phenomena · Physics 2020-06-05 Dipanweeta Bhattacharyya , A. Mangalam

In large scale cosmological hydrodynamic simulations simplified sub-grid models for gas accretion onto black holes and AGN feedback are commonly used. Such models typically depend on various free parameters, which are not well constrained.…

Astrophysics of Galaxies · Physics 2015-06-22 Lisa K. Steinborn , Klaus Dolag , Michaela Hirschmann , M. Almudena Prieto , Rhea-Silvia Remus

The physical processes responsible of sweeping up the surrounding gas in the host galaxy of an AGN, and able in some circumstances to expel it from the galaxy, are not yet well known. The various mechanisms are briefly reviewed: quasar or…

Astrophysics of Galaxies · Physics 2015-06-22 F. Combes

We follow the evolution of the Black Hole mass function in the assumption that mass accretion onto a massive BH is the powering mechanism of AGN activity. With reasonable assumptions suggested by current knowledge, it is possible to…

Astrophysics · Physics 2007-05-23 Alessandro Marconi , Marco Salvati

The Active Galactic Nuclei In Cosmological Simulations (AGNICS) project includes AGN into the GalICS hybrid (N-body + semi-analytic) model to explore the quasar-galaxy link in a cosmological perspective. The key problems are the quasar…

Astrophysics · Physics 2009-11-13 A. Cattaneo , J. Blaizot , J. Devriendt , B. Guiderdoni

An accretion flow onto a supermassive black hole is the primary process powering quasars. However, a geometry of this flow is not well constrained. Both global MHD simulations and observations suggest that there are several emission…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-08 Aneta Siemiginowska

Black hole spins affect the efficiency of the "classical" accretion processes, hence the radiative output from quasars. Spins also determine how much energy is extractable from the hole itself. Recently it became clear that massive black…

High Energy Astrophysical Phenomena · Physics 2010-10-06 Marta Volonteri

For most of their lives, galaxies are surrounded by large and massive coronae of hot gas, which constitute vast reservoirs for gas accretion. This Chapter describes a mechanism that allows star-forming disc galaxies to extract gas from…

Astrophysics of Galaxies · Physics 2017-05-31 Filippo Fraternali

Supermassive black holes in galaxy centres can grow by the accretion of gas, liberating energy that might regulate star formation on galaxy-wide scales. The nature of the gaseous fuel reservoirs that power black hole growth is nevertheless…

We explore the connection between black hole growth at the center of obscured quasars selected from the XMM-COSMOS survey and the physical properties of their host galaxies. We study a bolometric regime (<Lbol > 8 x 10^45 erg/s) where…

There is an interesting correlation between the central objects and their host galaxies in recent high resolution HST photometry of early type galaxies and Near-IR images of nearby quasar hosts. It has been shown that a) the hosts of these…

Astrophysics · Physics 2007-05-23 Yiping Wang , Peter L. Biermann

Quasars are powered by accretion onto supermassive black holes, but the problem of the duty cycle related to the episodic activity of the black holes remains open as one of the major questions of cosmological evolution of quasars. In this…

Astrophysics · Physics 2009-11-11 Jian-Min Wang , Yan-Mei Chen , Fan Zhang

The mass density of massive black holes observed locally is consistent with the hard X-ray Background provided that most of the radiation produced during their growth was absorbed by surrounding gas. A simple model is proposed here for the…

Astrophysics · Physics 2009-10-31 A. C. Fabian

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