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Related papers: ADAFs -- Models, Observations and Problems

200 papers

We review basic properties of advection-dominated accretion flows (ADAFs) and their applications to astrophysical systems ranging from Galactic binary systems to galactic nuclei. A new classification scheme for low-luminosity, X-ray bright…

Astrophysics · Physics 2007-05-23 Insu Yi

A model for advection-dominated accretion flows (ADAFs) in a global magnetic field is proposed. In contrast to the well known ADAF models in which the viscosity of a fluid determines both angular momentum transfer and energy dissipation in…

Astrophysics · Physics 2009-10-31 Osamu Kaburaki

The standard Advection-Dominated Accretion Flow (ADAF) is studied using a set of self-similar analytical solutions in the spherical coordinates. Our new solutions are useful for studying ADAFs without dealing with the usual mathematical…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Mohsen Shadmehri

Recent work on advection-dominated accretion flows (ADAFs) is reviewed. The article concentrates on an optically thin branch of ADAFs which is present at mass accretion rates below a critical value $\sim(10^{-2}-10^{-1})$ the Eddington…

Astrophysics · Physics 2007-05-23 Ramesh Narayan

This article reviews the physics of advection-dominated accretion flows (ADAFs) and describes applications to several black hole X-ray binaries and galactic nuclei. The possibility of using ADAFs to explore the event horizons of black holes…

Astrophysics · Physics 2007-05-23 Ramesh Narayan , Rohan Mahadevan , Eliot Quataert

Using simple arguments we show that the canonical thin keplerian accretion disks cannot smoothly match any plain advection dominated flow (ADAF) model. By 'plain' ADAF model we mean the ones with zero cooling. The existence of sonic points…

Astrophysics · Physics 2016-08-30 D. Molteni , G. Gerardi , M. A. Valenza

Numerical, two-dimensional, time-dependent hydrodynamical models of geometrically thick accretion discs around black holes are presented. Accretion flows with non-effective radiation cooling (ADAFs) can be both convectively stable or…

Astrophysics · Physics 2009-09-25 Igor V. Igumenshchev

Recent papers discussing advection dominated accretion flows (ADAF) as a solution for astrophysical accretion problems should be treated with some caution because of their uncertain physical basis. The suggestions underlying ADAF involve…

Astrophysics · Physics 2009-10-31 G. S. Bisnovatyi-Kogan , R. V. E. Lovelace

The present study examines self-similarity evolution of advection dominated accretion flow (ADAF) in the presence of a toroidal magnetic field. In this research, it was assumed that the angular momentum transport is due to viscous…

High Energy Astrophysical Phenomena · Physics 2012-05-11 Alireza Khesali , Kazem Faghei

Radiatively inefficient (or advection dominated) disks are discussed at an introductory level. Ion supported and radiation supported flows are discussed, the different consequences of advection dominated flows onto black holes vs. solid…

Astrophysics · Physics 2007-05-23 H. C. Spruit

We present a modified description of advection-dominated accretion flows (ADAF) with a geometrical viscosity. A simplified treatment of the dynamics of the flow in the inner relativistic part is suggested and results are compared with the…

Astrophysics · Physics 2007-05-23 T. Beckert , W. J. Duschl

Recent numerical simulations of radiatively inefficient accretion flows onto compact objects have shown that convection is a general feature in such flows. Dissipation of rotational and gravitational energies in the accretion flows results…

Astrophysics · Physics 2009-11-06 Igor V. Igumenshchev , Marek A. Abramowicz

We calculate the radiation spectra from advection-dominated accretion flows (ADAFs), taking into account the effects of a global magnetic field. Calculation is based on the analytic model for magnetized ADAFs proposed by Kaburaki, where a…

Astrophysics · Physics 2009-10-31 Motoki Kino , Osamu Kaburaki , Naohiro Yamazaki

We study the thermal structure of the widely adopted two-dimensional advection dominated accretion flow (ADAF) of Narayan & Yi (1995a). The critical radius for a given mass accretion rate, outside of which the optically thin hot solutions…

Astrophysics · Physics 2009-10-31 Myeong-Gu Park , Jeremiah P. Ostriker

We solve the set of hydrodynamic (HD) equations for optically thin Advection Dominated Accretion Flows (ADAFs) by assuming radially self-similar in spherical coordinate system $ (r, \theta, \phi) $. The disk is considered to be steady state…

High Energy Astrophysical Phenomena · Physics 2015-11-12 Fateme Zahra Zeraatgari , Shahram Abbassi

We implement a new semi-analytical approach to investigate radially self-similar solutions for the steady-state advection-dominated accretion flows (ADAFs). We employ the usual $\alpha$-prescription for the viscosity and all the components…

High Energy Astrophysical Phenomena · Physics 2018-08-08 Asiyeh Habibi , Shahram Abbassi , Mohsen Shadmehri

We study the formation of the spectra in advection dominated accretion flows (ADAFs) around Kerr black holes. We use a Monte Carlo approach and fully general relativistic treatment to follow the paths of individual photons and model their…

Astrophysics · Physics 2007-05-23 A. Kurpiewski , M. Jaroszynski

Advection-dominated accretion flows (ADAFs) are known to be convectively unstable for low values of the viscosity parameter alpha. Two-dimensional axisymmetric hydrodynamic simulations of such flows reveal a radial density profile which is…

Astrophysics · Physics 2009-10-31 Igor V. Igumenshchev , Marek A. Abramowicz , Ramesh Narayan

General properties of advection-dominated accretion flows are discussed. Special emphasis is given to the optically thin branch of solutions, which has very high ion and electron temperatures and is thermally stable. This solution branch…

Astrophysics · Physics 2007-05-23 Ramesh Narayan

In a previous paper, we described new analytic formulae for optically-thick supercritical accretion flows (Watarai 2006, hereafter paper 1). Here we present analytic formulae for optically-thin one-temperature accretion flows including the…

Astrophysics · Physics 2015-06-24 Ken-ya Watarai
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