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Related papers: Wind from cold accretion flows

200 papers

Warm absorbers are present in many Active Galactic Nuclei (AGN), seen as mildly ionised gas outflowing with velocities of a few hundred to a few thousand kilometres per second. These slow velocities imply a large launch radius, pointing to…

High Energy Astrophysical Phenomena · Physics 2019-08-16 Misaki Mizumoto , Chris Done , Ryota Tomaru , Isaac Edwards

I review the main results from recent 2-D, time-dependent hydrodynamic models of radiation-driven winds from accretion disks in AGN. I also discuss the physical conditions needed for a disk wind to be shielded from the strong X-rays and to…

Astrophysics · Physics 2007-05-23 D. Proga

The ultraviolet (UV) bright accretion disc in active galactic nuclei (AGN) should give rise to line driving, producing a powerful wind which may play an important role in AGN feedback as well as in producing structures like the broad line…

High Energy Astrophysical Phenomena · Physics 2021-11-05 Arnau Quera-Bofarull , Chris Done , Cedric G. Lacey , Mariko Nomura , Ken Ohsuga

We explore consequences of a radiation driven disk wind model for mass outflows from active galactic nuclei (AGN). We performed axisymmetric time-dependent hydrodynamic calculations using the same computational technique as Proga, Stone and…

Astrophysics · Physics 2011-09-30 D. Proga , T. R. Kallman

Analysis of spectral absorption features has led to the identification of several distinct outflow components in AGNs. The outflowing gas is evidently photoionized by the nuclear continuum source and originates in the accretion flow toward…

Astrophysics · Physics 2007-05-23 Arieh Konigl

Ultra-fast outflows (UFOs) are mildly relativistic (outflow velocity $v_{out}>0.1c$) nuclear winds detected as blueshifted absorption lines from highly ionized, dense gas in the X-ray spectra of active galactic nuclei. The AGN feedback…

Winds are commonly observed in luminous active galactic nuclei (AGNs). A plausible model of those winds is magnetohydrodynamic (MHD) disc winds. In the case of disc winds from a thin accretion disc, isothermal or adiabatic assumption is…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Weixiao Wang , De-Fu Bu , Feng Yuan

We study outflows driven by Active Galactic Nuclei (AGNs) using high- resolution simulations of idealized z=2 isolated disk galaxies. Episodic accretion events lead to outflows with velocities >1000 km/s and mass outflow rates up to the…

Astrophysics of Galaxies · Physics 2015-06-18 Jared M. Gabor , Frédéric Bournaud

15 years of XMM-Newton observations have established that ultra-fast, highly ionized winds are common in radio-quiet AGN. A simple theory of Eddington-limited accretion correctly predicts the typical velocity (~0.1c) and high ionization of…

Astrophysics of Galaxies · Physics 2017-05-10 Ken Pounds , Andrew Lobban , Chris Nixon

Galaxy-scale outflows, which are thought to provide the link connecting the central black hole to its host galaxy, are now starting to be observed. However, the physical origin of the mechanism driving the observed outflows, whether due to…

Astrophysics of Galaxies · Physics 2015-08-06 W. Ishibashi , A. C. Fabian

Fast, massive winds are ubiquitously observed in the UV and X-ray spectra of Active Galactic Nuclei (AGN) and other accreting sources. Theoretical and observational evidences suggest they are launched at accretion disc scales, carrying…

High Energy Astrophysical Phenomena · Physics 2024-10-23 Alfredo Luminari , Enrico Piconcelli , Francesco Tombesi , Fabrizio Nicastro , Fabrizio Fiore

It is now widely accepted that most galaxies undergo an active phase, during which a central super-massive black hole generates vast radiant luminosities through the gravitational accretion of gas. Winds launched from a rotating accretion…

Astrophysics · Physics 2009-07-09 S. Young , D. J. Axon , A. Robinson , J. H. Hough , J. E. Smith

In order to reveal the origin of the ultra-fast outflows (UFOs) that are frequently observed in active galactic nuclei (AGNs), we perform two-dimensional radiation hydrodynamics simulations of the line-driven disk winds, which are…

High Energy Astrophysical Phenomena · Physics 2017-01-25 Mariko Nomura , Ken Ohsuga

We present the results of time-dependent hydrodynamic calculations of line- driven winds from accretion disks in AGN. To calculate the radiation force, we take into account radiation from the disk and the central engine. The gas temperature…

Astrophysics · Physics 2009-09-25 D. Proga , J. M. Stone , T. R. Kallman

We show, using global 3D grid-based hydrodynamical simulations, that Ultra Fast Outflows (UFOs) from Active Galactic Nuclei (AGN) result in considerable feedback of energy and momentum into the interstellar medium (ISM) of the host galaxy.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 A. Y. Wagner , M. Umemura , G. V. Bicknell

Highly-ionized fast accretion-disk winds have been suggested as an explanation for a variety of observed absorption and emission features in the X-ray spectra of Active Galactic Nuclei. Simple estimates have suggested that these flows may…

High Energy Astrophysical Phenomena · Physics 2015-05-18 S. A. Sim , L. Miller , K. S. Long , T. J. Turner , J. N. Reeves

I present a brief review of theory of winds in active galactic nuclei (AGN). Magnetic, radiation, and thermal driving likely operate in AGN. In many cases, it is difficult to distinguish, both from observational and theoretical point of…

Astrophysics · Physics 2007-05-23 Daniel Proga

Ultra-fast outflows (UFOs) are seen in many AGN, giving a possible mode for AGN feedback onto the host galaxy. However, the mechanism(s) for the launch and acceleration of these outflows are currently unknown, with UV line driving…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Kouichi Hagino , Hirokazu Odaka , Chris Done , Poshak Gandhi , Shin Watanabe , Masao Sako , Tadayuki Takahashi

Accretion disk winds are commonly observed in active galactic nuclei (AGN). The winds may be associated with the changing spectral properties of such sources, yet such connections have not been studied in detail so far. This paper presents…

Astrophysics of Galaxies · Physics 2025-04-29 Hagai Netzer

The role of star-formation driven outflows in the obscuration of the central source in the Active Galactic Nuclei (AGN) is discussed. The outflow from a sub-parsec scale accretion disc is numerically modelled for parameters appropriate to…

Astrophysics · Physics 2008-11-26 Sergei Nayakshin , Jorge Cuadra