A GLOBAL THREE-DIMENSIONAL RADIATION MAGNETO-HYDRODYNAMIC SIMULATION OF SUPER-EDDINGTON ACCRETION DISKS

By Y. Jiang 姜, James M. Stone, S. Davis. 2014

248 citations recorded by the source corpus.

We study super-Eddington accretion flows onto black holes using a global three-dimensional radiation magneto-hydrodynamical simulation. We solve the time-dependent radiative transfer equation for the specific intensities to accurately calculate the angular distribution of the emitted radiation. Turbulence generated by the magneto-rotational instability provides self-consistent angular momentum transfer. The simulation reaches inflow equilibrium with an accretion rate ∼220 LEdd/c2 and forms a radiation-driven outflow along the rotation axis. The mechanical energy flux carried by the outflow is ∼20% of the radiative energy flux. The total mass flux lost in the outflow is about 29% of the net accretion rate. The radiative luminosity of this flow is ∼10 LEdd. This yields a radiative efficiency ∼4.5%, which is comparable to the value in a standard thin disk model. In our simulation, vertical advection of radiation caused by magnetic buoyancy transports energy faster than photon diffusion, allowing a significant fraction of the photons to escape from the surface of the disk before being advected into the black hole. We contrast our results with the lower radiative efficiencies inferred in most models, such as the slim disk model, which neglect vertical advection. Our inferred radiative efficiencies also exceed published results from previous global numerical simulations, which did not attribute a significant role to vertical advection. We briefly discuss the implications for the growth of supermassive black holes in the early universe and describe how these results provided a basis for explaining the spectrum and population statistics of ultraluminous X-ray sources.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/738dab7121e66c9107abf61a844d158eec5f7d34

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Citations in the corpus

GENERAL RELATIVISTIC HYDRODYNAMIC SIMULATION OF ACCRETION FLOW FROM A STELLAR TIDAL DISRUPTION (2015, background): “…focused on the first step—how the orbital energy is dissipated—and we have done so by consciously ignoring MHD effects, which almost certainly are important to the last step (angular momentum transport) and possibly even to the middle step (heat loss: see Blaes et al. (2011); Jiang et al. (2014)).”
simba: Cosmological simulations with black hole growth and feedback (2019, methodology): “…we apply a limit of 3 times the Eddington rate, based on the idea that non-spherical accretion can potentially exceed Eddington as occasionally observed particularly at higher redshifts (Martınez-Aldama et al. 2018) and consistent with recent accretion disk simulations (e.g. Jiang et al. 2014).”
Neutrino-dominated accretion flows as the central engine of gamma-ray bursts (2017, methodology): “The results of Jiang et al. (2014) indicated that the radiation can be widely increased because of the vertical advection of radiation caused by magnetic buoyancy.”
The Athena++ Adaptive Mesh Refinement Framework: Design and Magnetohydrodynamic Solvers (2020, methodology): “…(Beckwith & Stone 2011), particles (Bai & Stone 2010a), sink particles (Gong & Ostriker 2013), a total energy conserving formalism for self-gravity (Jiang et al. 2013), and radiation transport (Skinner & Ostriker 2013; Davis et al. 2012; Jiang et al. 2012, 2014a), among many other features.”
A Unified Model for Tidal Disruption Events (2018, background): “Recently the development of novel radiation magnetohydrodynamics (MHD) codes, some of which also performed under full general relativity (GR), have helped us understand more about such accretion flow (e.g., Ohsuga et al. 2005; Jiang et al. 2014; McKinney et al. 2014; Sa̧dowski et al. 2015).”
Three-dimensional GRMHD Simulations of Neutrino-cooled Accretion Disks from Neutron Star Mergers (2017, background): “…energy generated by viscosity is locally dissipated in proportion to the gas density, numerical simulations of MHD disks show that a disproportionally large fraction of their “heating” occurs nonlocally through reconnection in low-density coronal regions (Hirose et al. 2006; Jiang et al. 2014a).”
Three-dimensional simulations of supercritical black hole accretion discs - luminosities, photon trapping and variability (2015, methodology): “This was later followed by codes using more advanced radiative transport schemes, either still in the Newtonian or special-relativistic approximation (Jiang et al. 2012, 2014a; Ohsuga & Takahashi 2015), or in general relativity (Sądowski et al. 2013; McKinney et al. 2014; Fragile et al. 2014).”
Titans of the early Universe: The Prato statement on the origin of the first supermassive black holes (2018, background): “Black holes accreting at rates above the Eddington limit have been shown to generate powerful jets (McKinney, Tchekhovskoy, & Blandford 2013; Sa̧dowski et al. 2014, 2016; Jiang et al. 2014) which may significantly disrupt the accretion flow.”
Cool outflows in galaxies and their implications (2020, unknown): “10−3 (e.g., Sadowski et al. 2013, 2014; Sadowski and Narayan 2015; Jiang et al. 2014; McKinney et al. 2014, 2015).”
An Embedded X-Ray Source Shines through the Aspherical AT 2018cow: Revealing the Inner Workings of the Most Luminous Fast-evolving Optical Transients (2018, background): “However, recent radiation MHD simulations of super-Eddington flows by Jiang et al. (2014) find that radiative efficiencies of ∼5% (similar to thin disks) are possible for flows accreting up to M22 Edd˙ , in the range relevant here.”
Rapid and Bright Stellar-mass Binary Black Hole Mergers in Active Galactic Nuclei (2016, background): “…accretion onto 10–100 M black holes can produce a fast, bright (super-Eddington) electromagnetic transients through the disk’s thermal emission Jiang et al. (2014); McKinney et al. (2014); Murase et al. (2016), and possibly through driving relativistic outflows (Remillard & McClintock 2006;…”
Circularization of Tidally Disrupted Stars around Spinning Supermassive Black Holes (2015, background): “…efficiency of these streams could be reduced if they cool to the point where bound-free absorption dominates electron scattering as a source of opacity (Kochanek 1994), but it could also be increased if magnetically driven turbulent advection of photons enhances cooling rates (Jiang et al. 2014).”
A bright year for tidal disruptions (2015, methodology): “…Events 5 η ≈ 0.05 for a non-rotating BH was found by radiation (magneto)hydrodynamical simulations of highly super-Eddington disk accretion (e.g. Jiang et al. 2014; see also Ohsuga et al. 2005; Sadowski & Narayan 2015; Jiao et al. 2015), when both radiative and kinetic luminosity are…”