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相关论文: 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…

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…

星系天体物理 · 物理学 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…

天体物理学 · 物理学 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…

宇宙学与河外天体物理 · 物理学 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…

天体物理学 · 物理学 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…

星系天体物理 · 物理学 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…

高能天体物理现象 · 物理学 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.…

星系天体物理 · 物理学 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…

星系天体物理 · 物理学 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…

天体物理学 · 物理学 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…

天体物理学 · 物理学 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…

宇宙学与河外天体物理 · 物理学 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…

高能天体物理现象 · 物理学 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…

星系天体物理 · 物理学 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…

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…

天体物理学 · 物理学 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…

天体物理学 · 物理学 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…

天体物理学 · 物理学 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…

天体物理学 · 物理学 2009-11-10 Guinevere Kauffmann , Timothy Heckman