Abstract
Quasars are powered by supermassive black hole (SMBH) accretion disks, yet standard thin disk models are inconsistent with many observations. Recently, P. F. Hopkins et al. simulated the formation of a quasar disk feeding an SMBH of mass M = 1.3 × 107 M⊙ in a galaxy. The disk had surprisingly strong toroidal magnetic fields that supported it vertically from gravity and powered rapid accretion. What feedback can such a system produce? To answer this, we must follow the gas to the event horizon. For this, we interpolated the quasar into the general-relativistic radiation magnetohydrodynamics code H-AMR and performed 3D simulations with BH spins a = 0 and a = 0.9375. This remapping generates magnetic monopoles, which we erase using a novel divergence cleaning approach. Despite the toroidal magnetic field's dominance at large radii, vertical magnetic flux builds up near the event horizon, leading to a magnetic state transition within the inner 200 gravitational radii of the disk. This powers strong winds and, for spinning BHs, relativistic jets that can spin down the BH within 5−10 Myr. Sometimes, vertical magnetic fields of opposite polarity reach the BH, causing a polarity inversion event that briefly destroys the jets and, possibly, the X-ray corona. These strong fields power accretion at rates 5× the Eddington limit, which can double the BH mass in 5-10 Myr. When a = 0.9375 (a = 0), the energy in mechanical outflows and radiation equals about 60% (10%) and 100% (3%) of the accreted rest mass energy, respectively. Much of the light escapes in cool, ≳1300 au photospheres, consistent with quasar microlensing and spectral energy distributions.
| Original language | English (US) |
|---|---|
| Article number | 248 |
| Journal | Astrophysical Journal |
| Volume | 979 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 1 2025 |
Funding
We thank Minghao Guo, Eliot Quataert, and Ethan Vishniac for useful conversations. N.K. is supported by an NSF Graduate Research Fellowship. M.L. was supported by the John Harvard, ITC, and NASA Hubble Fellowship Program fellowships, and NASA ATP award 21-ATP21-0077. Support for P.F.H. was provided by NSF Research grants 20009234, 2108318, NASA grant 80NSSC18K0562, and a Simons Investigator award. A.T. acknowledges support by NASA 80NSSC22K0031, and 80NSSC18K0565 grants, and by the NSF grants AST-2107839, AST-1815304, AST-1911080, AST-2206471, AST-2407475, and OAC-2031997. J.J. and A.T. acknowledge support by the NSF AST-2009884, NASA 80NSSC21K1746, and NASA XMM-Newton 80NSSC22K0799 grants. This research was supported in part by grant NSF PHY-2309135 to the Kavli Institute for Theoretical Physics (KITP). An award of computer time was provided by the Innovative and Novel Computational Impact on Theory and Experiment (INCITE) and ASCR Leadership Computing Challenge (ALCC) programs under award AST178. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under contract No. DE-AC05-00OR22725. The authors acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing computational resources that have contributed to the research results reported within this paper.
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science