Non-axisymmetric instabilities in shocked adiabatic accretion flows

Abstract

We investigate the linear stability of a shocked accretion flow onto a black hole in the adiabatic limit. Our linear analyses and numerical calculations show that, despite the post-shock deceleration, the shock is generally unstable to non-axisymmetric perturbations. The simulation results of Molteni, Tóth & Kuznetsov can be well explained by our linear eigenmodes. The mechanism of this instability is confirmed to be based on the cycle of acoustic waves between the corotation radius and the shock. We obtain an analytical formula to calculate the oscillation period from the physical parameters of the flow. We argue that the quasi-periodic oscillation should be a common phenomenon in accretion flows with angular momentum.

14 pages, 7 figures, accepted for publication in MNRAS

References in corpus (9)

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Cited by in corpus (10)

• General Relativistic Hydrodynamic Simulations and Linear Analysis of the Standing Accretion Shock Instability around a Black Hole
• Simulations of Viscous Accretion Flow around Black Holes in Two-Dimensional Cylindrical Geometry
• The Standing Accretion Shock Instability in the Disk around the Kerr Black Hole
• The role of flow geometry in influencing the stability criteria for low angular momentum axisymmetric black hole accretion
• General Relativistic Numerical Simulation of sub-Keplerian Transonic Accretion Flows onto Black Holes: Schwarzschild Spacetime
• Standing Shock Instability in Advection-Dominated Accretion Flows
• Effects of resistivity on standing shocks in low angular momentum flows around black holes
• Direct time radio variability induced by non-axisymmetric standing accretion shock instability: implications for M87
• Collapsar Disk Outflows III: Detectable Neutrino and Gravitational Wave Signatures
• On the stability of isothermal shocks in black hole accretion disks