SIMULATIONS OF VISCOUS ACCRETION FLOW AROUND BLACK HOLES IN A TWO-DIMENSIONAL CYLINDRICAL GEOMETRY

Journal Article · Tue Nov 01 00:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/831/1/33· OSTI ID:22667278

Lee, Seong-Jae; Hyung, Siek ^[1]; Chattopadhyay, Indranil; Kumar, Rajiv ^[2]; Ryu, Dongsu ^[3]

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1. School of Science Education (Astronomy), Chungbuk National University, Chungbuk 28644 (Korea, Republic of)
2. ARIES, Manora Peak, Nainital-263002, Uttarakhand (India)
3. Department of Physics, School of Natural Sciences UNIST, Ulsan 44919 (Korea, Republic of)

We simulate shock-free and shocked viscous accretion flows onto a black hole in a two-dimensional cylindrical geometry, where initial conditions were chosen from analytical solutions. The simulation code used the Lagrangian total variation diminishing plus remap routine, which enabled us to attain high accuracy in capturing shocks and to handle the angular momentum distribution correctly. The inviscid shock-free accretion disk solution produced a thick disk structure, while the viscous shock-free solution attained a Bondi-like structure, but in either case, no jet activity nor any quasi-periodic oscillation (QPO)-like activity developed. The steady-state shocked solution in the inviscid as well as in the viscous regime matched theoretical predictions well. However, increasing viscosity renders the accretion shock unstable. Large-amplitude shock oscillation is accompanied by intermittent, transient inner multiple shocks. This oscillation of the inner part of the disk is interpreted as the source of QPO in hard X-rays observed in micro-quasars. Strong shock oscillation induces strong episodic jet emission. The jets also show the existence of shocks, which are produced as one shell hits the preceding one. The periodicities of the jets and shock oscillation are similar; the jets for the higher viscosity parameter appear to be stronger and faster.

• OSTI ID: 22667278
• Journal Information: Astrophysical Journal, Vol. 831, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCRETION DISKS
ACCURACY
AMPLITUDES
ANALYTICAL SOLUTION
ANGULAR MOMENTUM
BLACK HOLES
DISTRIBUTION
EMISSION
HARD X RADIATION
HYDRODYNAMIC MODEL
INSTABILITY
LAGRANGIAN FUNCTION
OSCILLATIONS
PERIODICITY
QUASARS
SIMULATION
TRANSIENTS
TWO-DIMENSIONAL CALCULATIONS
VISCOSITY