Stability of general-relativistic accretion disks

Journal Article · Tue Feb 15 04:00:00 EST 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.83.043007· OSTI ID:21504951

Korobkin, Oleg ^[1]; Abdikamalov, Ernazar B ^[2]; Schnetter, Erik ^[2]; Stergioulas, Nikolaos ^[3]; Zink, Burkhard ^[4]

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1. Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)
2. Center for Computation and Technology, Louisiana State University, Baton Rouge, Louisiana 70803 (United States)
3. Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, 54124 Greece (Greece)
4. Theoretical Astrophysics, University of Tuebingen, Tuebingen 72076 (Germany)

Self-gravitating relativistic disks around black holes can form as transient structures in a number of astrophysical scenarios such as binary neutron star and black hole-neutron star coalescences, as well as the core collapse of massive stars. We explore the stability of such disks against runaway and nonaxisymmetric instabilities using three-dimensional hydrodynamics simulations in full general relativity using the Thor code. We model the disk matter using the ideal fluid approximation with a {Gamma}-law equation of state with {Gamma}=4/3. We explore three disk models around nonrotating black holes with disk-to-black hole mass ratios of 0.24, 0.17, and 0.11. Because of metric blending in our initial data, all of our initial models contain an initial axisymmetric perturbation which induces radial disk oscillations. Despite these oscillations, our models do not develop the runaway instability during the first several orbital periods. Instead, all of the models develop unstable nonaxisymmetric modes on a dynamical time scale. We observe two distinct types of instabilities: the Papaloizou-Pringle and the so-called intermediate type instabilities. The development of the nonaxisymmetric mode with azimuthal number m=1 is accompanied by an outspiraling motion of the black hole, which significantly amplifies the growth rate of the m=1 mode in some cases. Overall, our simulations show that the properties of the unstable nonaxisymmetric modes in our disk models are qualitatively similar to those in the Newtonian theory.

• OSTI ID: 21504951
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 4 Vol. 83; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
79 ASTRONOMY AND ASTROPHYSICS
ACCRETION DISKS
APPROXIMATIONS
ASTROPHYSICS
AXIAL SYMMETRY
BLACK HOLES
CALCULATION METHODS
COALESCENCE
ENERGY RANGE
EQUATIONS
EQUATIONS OF STATE
FIELD THEORIES
FLUID MECHANICS
GENERAL RELATIVITY THEORY
HYDRODYNAMICS
INSTABILITY
MASS
MECHANICS
METRICS
MIXING
NEUTRON STARS
OSCILLATIONS
PERTURBATION THEORY
PHYSICS
RELATIVISTIC RANGE
RELATIVITY THEORY
SIMULATION
STABILITY
STARS
SYMMETRY
TRANSIENTS