Improving Black Hole Accretion Treatment in Hydrodynamical Simulations

Abstract

The large galactic scales are connected to the many orders of magnitude smaller supermassive black hole (SMBH) scales by an episodic cycle of feeding and feedback. Active galactic nuclei (AGN) are powered by accretion onto SMBH and the majority of AGN energy, in near-Eddington regime, is produced in thin sub-pc accretion discs. Currently, it is very difficult to model processes that occur on vastly different scales, ranging from the circumnuclear gas reservoirs at tens to hundreds of parsecs, down to the accretion disc scales at <0.01 pc. While sub-grid prescriptions used in large-scale or cosmological simulations are able to reproduce large-scale feedback, we propose using a more realistic model in parsec-scale simulations, where it is important to get accurate timescales to understand how feedback affects gas dynamics and star formation in the vicinity of the AGN. To test our approach we use a sub-resolution thin accretion disc model, coupled to the SMBH, in a set of hydrodynamical simulations of a retrograde collision between a gas ring and a molecular cloud in an environment similar to the Galactic centre using the SPH code Gadget-3. The disc-mediated feeding of the SMBH is relatively smooth and delayed compared to an instantaneous feeding prescription. While the reduction of accretion due to feedback is present in both accretion disc and instantaneous feeding simulations, a clear central cavity appears only in accretion disc runs - hinting that a less volatile accretion phase could have a greater impact on the surrounding gas.

19 pages, 18 figures; accepted for publication in MNRAS; The Python implementation of the accretion disc particle method is available at https://github.com/Caradryan/accretiondisc

References in corpus (22)

• Array Programming with NumPy
• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• Simba: Cosmological Simulations with Black Hole Growth and Feedback
• Giant Gamma-ray Bubbles from Fermi-LAT: AGN Activity or Bipolar Galactic Wind?
• Stellar Feedback in Dwarf Galaxy Formation
• An Improved Distance and Mass Estimate for Sgr A* from a Multistar Orbit Analysis
• Detection of large-scale X-ray bubbles in the Milky Way halo
• A refined sub-grid model for black hole accretion and AGN feedback in large cosmological simulations
• Ionized outflows from active galactic nuclei as the essential elements of feedback
• Star Formation Around Super-Massive Black Holes
• Linking Macro, Meso, and Micro Scales in Multiphase AGN Feeding and Feedback
• ALMA images the many faces of the NGC1068 torus and its surroundings
• The Galactic Centre Chimney
• Mass inflow rate into the Central Molecular Zone: observational determination and evidence of episodic accretion
• The importance of dry and wet merging on the formation and evolution of elliptical galaxies
• The Effect of the AGN Feedback on the Interstellar Medium of Early-Type Galaxies: 2D Hydrodynamical Simulations of the Low-Rotation Case
• Black hole feeding and feedback: the physics inside the "subgrid"
• From kpcs to the central parsec of NGC 1097: feeding star formation and a black hole at the same time
• Feeding of active galactic nuclei by dynamical perturbations
• Multi-scale feedback and feeding in the closest radio galaxy Centaurus A