Magnetized Accretion onto and Feedback from Supermassive Black Holes in Elliptical Galaxies
Year: 2024
Type: article
Abstract: We present 3D magnetohydrodynamic simulations of the fueling of supermassive black holes in elliptical galaxies from a turbulent cooling medium on galactic scales, taking M87* as a typical case. We find that the mass accretion rate is increased by a factor of ∼10 compared with analogous hydrodynamic simulations. The scaling of M ̇ ∼ r 1 / 2 roughly holds from ∼10 pc to ∼10−3 pc (∼10 r g) with the accretion rate through the event horizon being ∼10−2 M ⊙ yr−1. The accretion flow on scales ∼0.03–3 kpc takes the form of magnetized filaments. Within ∼30 pc, the cold gas circularizes, forming a highly magnetized (β ∼ 10−3) thick disk supported by a primarily toroidal magnetic field. The cold disk is truncated and transitions to a turbulent hot accretion flow at ∼0.3 pc (103 r g). There are strong outflows toward the poles driven by the magnetic field. The outflow energy flux increases with smaller accretor size, reaching ∼3 × 1043 erg s−1 for r in = 8 r g; this corresponds to a nearly constant energy feedback efficiency of η ∼ 0.05–0.1 independent of accretor size. The feedback energy is enough to balance the total cooling of the M87/Virgo hot halo out to ∼50 kpc. The accreted magnetic flux at small radii is similar to that in magnetically arrested disk models, consistent with the formation of a powerful jet on horizon scales in M87. Our results motivate a subgrid model for accretion in lower-resolution simulations in which the hot gas accretion rate is suppressed relative to the Bondi rate by ∼ ( 10 r g / r B ) 1 / 2 .
Source: The Astrophysical Journal
Institutions: Princeton University, Institute for Advanced Study
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Awards: G1453181110, G1693976111, Track 4: Advanced CI Coordination Ecosystem: Monitoring and Measurement Services, Collaborative Research: CDS&E: Constraining the uncertain physics of galaxy formation: cosmic rays, black holes, and beyond, G2803462237, G2815302120, G3339971651, G3562386289, Track 1: ACCESS Resource Allocations Marketplace and Platform Services (RAMPS), G4010157413, G4248962021, ACO: An Open CI Ecosystem to Advance Scientific Discovery (OpenCI), Track 3: COre National Ecosystem for CyberinfrasTructure (CONECT), G5367127336, G5464919783, G6128126499, Track 2: Customized Multi-tier Assistance, Training, and Computational Help (MATCH) for End User ACCESS to CI, G8889403961
OpenAlex ID: W4402926145