Quick search Find article
Quick search
Find article

Accretion of Low Angular Momentum Material onto Black Holes: Two-dimensional Magnetohydrodynamic Case

FREE

Daniel Proga1 and Mitchell C. Begelman1,2

Show affiliations


We report on the second phase of our study of slightly rotating accretion flows onto black holes. We consider magnetohydrodynamical (MHD) accretion flows with a spherically symmetric density distribution at the outer boundary but with spherical symmetry broken by the introduction of a small, latitude-dependent angular momentum and a weak radial magnetic field. We study accretion flows by means of numerical two-dimensional, axisymmetric, MHD simulations with and without resistive heating. Our main result is that the properties of the accretion flow depend mostly on an equatorial accretion torus that is made of the material that has too much angular momentum to be accreted directly. The torus accretes, however, because of the transport of angular momentum due to the magnetorotational instability (MRI). Initially, accretion is dominated by the polar funnel, as in the hydrodynamic inviscid case, where material has zero or very low angular momentum. At the later phase of the evolution, the torus thickens toward the poles and develops a corona or an outflow or both. Consequently, the mass accretion through the funnel is stopped. The accretion of rotating gas through the torus is significantly reduced compared with the accretion of nonrotating gas (i.e., the Bondi rate). It is also much smaller than the accretion rate in the inviscid, weakly rotating case. Our results do not change if we switch on or off resistive heating. Overall our simulations are very similar to those presented by Stone, Pringle, Hawley, and Balbus despite different initial and outer boundary conditions. Thus, we confirm that MRI is very robust and controls the nature of radiatively inefficient accretion flows. Although the time-averaged properties of our models approach a steady state, we find that the instantaneous mass-accretion rate in the latter stages of our simulations is highly time-dependent, with the inner flow displaying three generic flow patterns.


Subject headings

accretion, accretion disks; black hole physics; galaxies: active; galaxies: nuclei; methods: numerical; MHD


Dates

Issue 2 (2003 August 1)

Received 2003 February 20, accepted for publication 2003 April 7



  1. Accretion of Low Angular Momentum Material onto Black Holes: Two-dimensional Magnetohydrodynamic Case

    Daniel Proga and Mitchell C. Begelman 2003 ApJ 592 767

  2. Local structure and magnetic properties of Fe60Co40 mechanical alloy

    Dong-Seok Yang et al 2009 J. Phys.: Conf. Ser. 190 012139

  3. Dynamical algebra and Dirac quantum modes in the Taub-NUT background

    Ion I Cotaescu and Mihai Visinescu 2001 Class. Quantum Grav. 18 3383

  4. Monte Carlo aided room scatter corrections in the air-kerma strength standardization of 169Yb and 60Co brachytherapy sources

    T Palani Selvam et al 2003 Phys. Med. Biol. 48 N139

  5. Conservative estimation of whole-body-averaged SARs in infants with a homogeneous and simple-shaped phantom in the GHz region

    Akimasa Hirata et al 2008 Phys. Med. Biol. 53 7215

  6. Perturbation theory for the nonlinear Schrödinger equation with a random potential

    Shmuel Fishman et al 2009 Nonlinearity 22 2861

  7. Neutrino–nucleus reactions and nuclear structure

    E Kolbe et al 2003 J. Phys. G: Nucl. Part. Phys. 29 2569

  8. Non-convergence of formal integrals of motion

    G Contopoulos et al 2003 J. Phys. A: Math. Gen. 36 8639

  9. Basic Sturm–Liouville problems

    M H Annaby and Z S Mansour 2005 J. Phys. A: Math. Gen. 38 3775

  10. Strongly coupled three-dimensional finite element transducer

    Ilya Avdeev et al 2004 J. Micromech. Microeng. 14 1491

Users also read

What's this?
This innovative new feature generates a list of articles 'also read' by other users based on them reading the original article. Article abstracts citations and references are all considered and weighted accordingly. We hope that this will help you find relevant papers for your research.

  1. Accretion of Low Angular Momentum Material onto Black Holes: Two-dimensional Hydrodynamical Inviscid Case
  2. Three-dimensional Magnetohydrodynamic Simulations of Radiatively Inefficient Accretion Flows
  3. Dynamics of Accretion Flows Irradiated by a Quasar
More

View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.