On the fate of gas accreting at a low rate on to a black hole

Gas supplied conservatively to a black hole at rates well below the Eddington rate may not be able to radiate effectively and the net energy flux, including the energy transported by the viscous torque, is likely to be close to zero at all radii. This has the consequence that the gas accretes with positive energy so that it may escape. Accordingly, we propose that only a small fraction of the gas supplied actually falls on to the black hole, and that the binding energy it releases is transported radially outward by the torque so as to drive away the remainder in the form of a wind. This is a generalization of and an alternative to an `ADAF' solution. Some observational implications and possible ways to distinguish these two types of flow are briefly discussed.

[1]  S. Chakrabarti Observational Evidence for Black Holes in the Universe , 2008 .

[2]  L. Ho in Observational Evidence for Black Holes in the Universe , 1999 .

[3]  S. Mineshige,et al.  Black-Hole Accretion Disks , 1999 .

[4]  R. Mahadevan,et al.  Reconciling the spectrum of Sagittarius A* with a two-temperature plasma model , 1998, Nature.

[5]  A. Gruzinov Radiative Efficiency of Collisionless Accretion , 1997, astro-ph/9710132.

[6]  C. Gammie,et al.  Advection-dominated Accretion Flows in the Kerr Metric. I. Basic Equations , 1997, astro-ph/9705117.

[7]  E. Quataert Particle Heating by Alfvénic Turbulence in Hot Accretion Flows , 1997, astro-ph/9710127.

[8]  R. Narayan,et al.  Advection-Dominated Accretion and the Spectral States of Black Hole X-Ray Binaries: Application to Nova Muscae 1991 , 1997, astro-ph/9705237.

[9]  R. Lovelace,et al.  Influence of Ohmic Heating on Advection-dominated Accretion Flows , 1997, astro-ph/9704208.

[10]  J. Loveday The Local Space Density of Dwarf Galaxies , 1997, astro-ph/9703022.

[11]  Reinhard Genzel,et al.  Stellar proper motions in the central 0.1 PC of the galaxy , 1997 .

[12]  I. Igumenshchev,et al.  NUMERICAL SIMULATION OF THICK DISC ACCRETION ON TO A ROTATING BLACK HOLE , 1997 .

[13]  Fulvio Melia,et al.  Accretion Disk Evolution with Wind Infall. I. General Solution and Application to Sagittarius A* , 1996, astro-ph/9611095.

[14]  R. Narayan,et al.  Global Structure and Dynamics of Advection-dominated Accretion Flows around Black Holes , 1996, astro-ph/9607019.

[15]  J. Hawley,et al.  Instability, turbulence, and enhanced transport in accretion disks , 1997 .

[16]  J. Lasota,et al.  Advection-Dominated Accretion Flows Around Kerr Black Holes , 1996, astro-ph/9607021.

[17]  W. Junor,et al.  The radio jet in 3C274 at 0.01 PC resolution , 1995 .

[18]  O. Regev,et al.  Thermal equilibria of accretion disks , 1994, astro-ph/9409018.

[19]  R. Narayan,et al.  Advection-dominated Accretion: Self-Similarity and Bipolar Outflows , 1994, astro-ph/9411058.

[20]  R. Narayan,et al.  Advection-dominated Accretion: A Self-similar Solution , 1994, astro-ph/9403052.

[21]  A. Koenigl Disk accretion onto magnetic T Tauri stars , 1991 .

[22]  J. Buchler,et al.  The structure of the thermal modes in pulsating stars , 1986 .

[23]  T. Snow,et al.  Observations of neutral atoms in the Rho Ophiuchi cloud , 1986 .

[24]  E. Sion,et al.  On the evolutionary state of cataclysmic variable white dwarfs and their recurrence times , 1986 .

[25]  A. Borysow,et al.  Theoretical Collision-induced Rototranslational Absorption Spectra for Modeling Titan's Atmosphere: H 2--N 2 Pairs , 1986 .

[26]  D. B. Friend,et al.  Polarization in massive X-ray binaries. I - A low-inclination model for Cygnus X-1 , 1986 .

[27]  M. Morris,et al.  The large system of molecular clouds in Orion and Monoceros , 1986 .

[28]  J. Silk,et al.  Dwarf galaxies, cold dark matter, and biased galaxy formation , 1986 .

[29]  R. Blandford,et al.  Hydromagnetic flows from accretion discs and the production of radio jets , 1982 .

[30]  D. Meier,et al.  Thick accretion disks - Self-similar, supercritical models , 1982 .

[31]  E. Phinney,et al.  Ion-supported tori and the origin of radio jets , 1982, Nature.

[32]  S. Ichimaru Bimodal behavior of accretion disks: Theory and application to Cygnus X-1 transitions , 1977 .

[33]  D. Lynden-Bell,et al.  The Evolution of viscous discs and the origin of the nebular variables. , 1974 .

[34]  J. Pain,et al.  Fluid Dynamics , 1967, Nature.

[35]  H. Bondi,et al.  On spherically symmetrical accretion , 1952 .