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Related papers: A Model for Quasi-Spherical Magnetized Accretion F…

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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

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 consider the accretion process in a disk with magnetic fields that are dragged in from the interstellar medium by gravitational collapse. Two diffusive processes are at work in the system: (1) "viscous" torques exerted by turbulent and…

The main aim of this paper is studying the effect of toroidal magnetic field on the structure of Advection-Dominated Accretion Flows (ADAF) in the presence of the turbulence viscosity and diffusivity due to viscosity and magnetic field…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Amin Mosallanezhad , Shahram Abbassi , Nasim Beiranvand

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

Spherical (nonrotating) accretion flows with small-scale magnetic fields have been investigated using three-dimensional, time-dependent MHD simulations. These simulations have been designed to model high-resolution (quasi) steady accretion…

Astrophysics · Physics 2008-11-26 Igor V. Igumenshchev

Observations of X-ray luminous elliptical galaxies suggest that the accretion rate onto the central supermassive black hole can reach a substantial fraction of the Bondi rate. However, classical accretion theory applicable to such hot…

High Energy Astrophysical Phenomena · Physics 2026-02-02 Cheng-Liang Jiao , Liying Zhu , Er-gang Zhao , Xiang-dong Shi

An analytic solution is presented to the three-dimensional problem of steady axisymmetric fluid flow through an accretion disk. The solution has been obtained through a systematic expansion in the small parameter epsilon =H/R (the ratio of…

Astrophysics · Physics 2007-05-23 W. Kluzniak , D. Kita

We develop and discuss a model formalism to study the properties of mass outflows that are emerged out from a relativistic, magnetized, viscous, advective accretion flow around a rotating black hole. In doing so, we consider the toroidal…

High Energy Astrophysical Phenomena · Physics 2024-04-08 Camelia Jana , Santabrata Das

The magnetically arrested disks (MADs) have attracted much attention in recent years. The formation of MADs are usually attributed to the accumulation of a sufficient amount of dynamically significant poloidal magnetic flux. In this work,…

High Energy Astrophysical Phenomena · Physics 2024-11-28 Jia-Wen Li , Xinwu Cao

We investigated effects on flow variables of transonic advection-dominated accretion flows (ADAFs) for different outer boundary locations (BLs) with a changing energy constant ($E$) of the flow. We used the ADAF solutions and investigated a…

High Energy Astrophysical Phenomena · Physics 2019-05-15 Rajiv Kumar , Wei-Min Gu

Outflows and convective motions in accretion flows have been intensively discussed recently in the context of advection-dominated accretion flow (ADAF) based on two-dimensional (2D) and three-dimensional (3D) hydrodynamical simulations. We,…

Astrophysics · Physics 2007-05-23 Mami Machida , Ryoji Matsumoto , and Shin Mineshige

The first spherical accretion model was developed 55 years ago, but the theory is yet far from being complete. The real accretion flow was found to be time-dependent and turbulent. This paper presents the minimal MHD spherical accretion…

Astrophysics · Physics 2009-11-13 Roman V. Shcherbakov

We study the time evolution of a large-scale magnetic flux threading an accretion disk. Induction equation of the mean poloidal field is solved under the standard viscous disk model. Magnetic flux evolution is controlled by the two…

Earth and Planetary Astrophysics · Physics 2015-06-17 Taku Takeuchi , Satoshi Okuzumi

Two significant progresses have been made in the past years on our understanding of hot accretion flows. One is that only a small fraction of accretion flow available at the outer boundary can finally falls onto the black hole while most of…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Fu-Guo Xie , Feng Yuan

Within the magnetospheric radius, the geometry of accretion flow in X-ray pulsars is shaped by a strong magnetic field of a neutron star. Starting at the magnetospheric radius, accretion flow follows field lines and reaches the stellar…

High Energy Astrophysical Phenomena · Physics 2024-02-21 A. A. Mushtukov , A. Ingram , V. F. Suleimanov , N. DiLullo , M. Middleton , S. S. Tsygankov , M. van der Klis , S. Portegies Zwart

We present a magneto-hydrodynamic model developed for investigations of advective non-stationary, asymmetric Keplerian accretion disks in the normal magnetic field. The introduced model allows us to trace the evolution in different fixed…

High Energy Astrophysical Phenomena · Physics 2014-08-19 Krasimira Yankova , Lachezar Filipov

We present a systematic, analytical study of geometrically thin, optically thick accretion disc solutions for magnetized turbulent flows, with an alpha-like viscosity prescription. Under the only assumptions that (1) Magneto-Rotational…

Astrophysics · Physics 2009-11-07 A. Merloni

We investigated the instability of advective accretion flow as a consequence of angular momentum transfer in one-dimensional, quasi-spherical transonic accretion flow around a non-rotating black hole. The code is designed to include the…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-09 Seong-Jae Lee , Dongsu Ryu , Indranil Chattopadhyay

In a series of our previous works, a model of radiatively inefficient accretion flows (RIAFs) in a global magnetic field (so called resistive RIAF model) has proved its ability to account for many physical processes taking place in such…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Osamu Kaburaki