NUMERICAL SIMULATIONS OF OPTICALLY THICK ACCRETION ONTO A BLACK HOLE. I. SPHERICAL CASE

Journal Article · Wed Aug 01 00:00:00 EDT 2012 · Astrophysical Journal, Supplement Series

DOI:https://doi.org/10.1088/0067-0049/201/2/9· OSTI ID:22047702

Fragile, P Chris; Gillespie, Anna; Monahan, Timothy; Rodriguez, Marco ^[1]; Anninos, Peter ^[2]

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1. Department of Physics and Astronomy, College of Charleston, Charleston, SC 29424 (United States)
2. Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA 94550 (United States)

Modeling the radiation generated by accreting matter is an important step toward realistic simulations of black hole accretion disks, especially at high accretion rates. To this end, we have recently added radiation transport to the existing general relativistic magnetohydrodynamic code, Cosmos++. However, before attempting to model radiative accretion disks, we have tested the new code using a series of shock tube and Bondi (spherical inflow) problems. The four radiative shock tube tests, first presented by Farris et al., have known analytic solutions, allowing us to calculate errors and convergence rates for our code. The Bondi problem only has an analytic solution when radiative processes are ignored, but it is pertinent because it is closer to the physics we ultimately want to study. In our simulations, we include Thomson scattering and thermal bremsstrahlung in the opacity, focusing exclusively on the super-Eddington regime. Unlike accretion onto bodies with solid surfaces, super-Eddington accretion onto black holes does not produce super-Eddington luminosity. In our examples, despite accreting at up to 300 times the Eddington rate, our measured luminosity is always several orders of magnitude below Eddington.

• OSTI ID: 22047702
• Journal Information: Astrophysical Journal, Supplement Series, Vol. 201, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCRETION DISKS
ANALYTICAL SOLUTION
ASTROPHYSICS
BLACK HOLES
BREMSSTRAHLUNG
COMPUTERIZED SIMULATION
CONVERGENCE
LUMINOSITY
MAGNETOHYDRODYNAMICS
OPACITY
RADIANT HEAT TRANSFER
RADIATION TRANSPORT
RELATIVISTIC RANGE
SHOCK TUBES
SPHERICAL CONFIGURATION
THOMSON SCATTERING
UNIVERSE