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Related papers: Dynamics of Magnetized Spherical Accretion Flows

200 papers

In this paper, we initiate a new study of steady funnel-flow accretion onto strongly magnetized neutron stars, including a full treatment of shock generation. As a first step, we adopt a simplified model considering the flow within…

Astrophysics · Physics 2009-06-23 Shigeyuki Karino , Motoki Kino , John C. Miller

The role of turbulence in a spherically symmetric accreting system has been studied on very large spatial scales of the system. This is also a highly subsonic flow region and here the accreting fluid has been treated as nearly…

Astrophysics · Physics 2009-11-10 Arnab K. Ray , J. K. Bhattacharjee

Equilibrium eigenstates of an axisymmetric magnetically confined plasma with toroidal flow are investigated by means of exact solutions of the ideal magnetohydrodynamic equations. The study includes "compressible" flows with constant…

Plasma Physics · Physics 2007-05-23 G. Poulipoulis , George Throumoulopoulos , Henri Tasso

We present results from our magnetohydrodynamical simulations of accretion flows onto black holes. Our main focus is the interplay between inflows and related outflows. We consider applications of such flows to the Galatic center and low…

Astrophysics · Physics 2009-11-10 Daniel Proga

We analytically study how the behaviour of accretion flows changes when the flow model is varied. We study the transonic properties of the conical flow, a flow of constant height and a flow in vertical equilibrium and show that all these…

Astrophysics · Physics 2009-11-10 S. K. Chakrabarti , Santabrata Das

We investigate the evolution of magnetohydrodynamic/hydromagnetic perturbations in the presence of stochastic noise in rotating shear flows. The particular emphasis is the flows whose angular velocity decreases but specific angular momentum…

High Energy Astrophysical Phenomena · Physics 2013-07-24 Sujit K. Nath , Banibrata Mukhopadhyay , Amit K. Chattopadhyay

We present the structure of a low angular momentum accretion flows around rotating compact objects incorporating relativistic corrections up to the leading post-Newtonian order. To begin with, we formulate the governing post-Newtonian…

High Energy Astrophysical Phenomena · Physics 2024-05-09 Elham Nazari , Samik Mitra , Shahram Abbassi , Santabrata Das

Using two different pseudo-Schwarzschild potentials proposed by Artemova et. al,$^{1}$ we formulate and solve the equations governing spherically symmetric transonic inflow and outflow in presence of a relativistic hadronic pressure…

Astrophysics · Physics 2009-11-07 Tapas Kumar Das

Field-channelled accretion flows occur in a variety of astrophysical objects, including T Tauri stars,magnetic cataclysmic variables and X-ray pulsars. We consider a curvilinear coordinate system and derive a general hydrodynamic…

Astrophysics · Physics 2009-11-10 Joao B. G. Canalle , Curtis J. Saxton , Kinwah Wu , Mark Cropper , Gavin Ramsay

Comparison of horizon-scale observations of Sgr A* and M87* with numerical simulations has provided considerable insight in their interpretation. Most of these simulations are variations of the same physical scenario consisting of a…

High Energy Astrophysical Phenomena · Physics 2023-10-18 Hector R. Olivares S. , Monika A. Moscibrodzka , Oliver Porth

We investigate two-temperature accretion flows onto strongly magnetized compact stars. Matter is accreted in the form of an accretion disc upto the disc radius ($r_{\rm d}$), where, the magnetic pressure exceeds both the gas and ram…

High Energy Astrophysical Phenomena · Physics 2023-04-19 Shilpa Sarkar , Kuldeep Singh , Indranil Chattopadhyay , Philippe Laurent

A hydrodynamic formulation for accretion flow channeled by a dipolar magnetic field is constructed using a curvi-linear coordinate system natural to the field structure. We solve the hydrodynamic equations and determine the velocity,…

Astrophysics · Physics 2007-05-23 J. B. G. Canalle , Kinwah Wu , Mark Cropper , Gavin Ramsay , Curtis Saxton

Accretion disks are likely threaded by external vertical magnetic flux, which enhances the level of turbulence via the magnetorotational instability (MRI). Using shearing-box simulations, we find that such external magnetic flux also…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Xue-Ning Bai , James M. Stone

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 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…

We present the results of axisymmetric, time-dependent magnetohydrodynamic simulations of accretion flows around black holes. The calculations begin from a rotationally supported thick torus which contains a weak poloidal field. Accretion…

Astrophysics · Physics 2009-10-31 James M. Stone , James E. Pringle

Axisymmetric equilibria with incompressible flows of arbitrary direction are studied in the framework of magnetohydrodynamics under a variety of physically relevant side conditions. To this end a set of pertinent non-linear ODEs are…

Plasma Physics · Physics 2007-05-23 G. N. Throumoulopoulos , H. Tasso , G. Poulipoulis

It is shown that transonic plasma acceleration in the converging-diverging magnetic field (magnetic nozzle) follows the unique global solution which is fully defined by the magnetic field. Such solution, which was analytically obtained…

Plasma Physics · Physics 2025-07-07 N. Sheth , A. Smolyakov , J. Deguire , S. Pande , P. N. Yushmanov

The transonic phenomenon of black hole accretion and the existence of the photon sphere are the characteristics of strong gravitational fields near a black hole horizon. In this work, we study spherical accretion flow onto a general…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Sen Yang , Cheng Liu , Tao Zhu , Li Zhao , Qiang Wu , Ke Yang , Mubasher Jamil

An accretion flow is necessarily transonic around a black hole. However, around a neutron star it may or may not be transonic, depending on the inner disk boundary conditions influenced by the neutron star. I will discuss various transonic…

Astrophysics · Physics 2009-11-13 Banibrata Mukhopadhyay