Strongly magnetized accretion discs require poloidal flux

Abstract

Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To this end, we perform local simulations of accretion discs with an initially purely toroidal magnetic field of equipartition strength. We demonstrate that discs with zero net vertical magnetic flux and realistic boundary conditions cannot sustain a strong toroidal field. However, a magnetic pressure-dominated disc can form from an initial configuration with a sufficient amount of net vertical flux and realistic boundary conditions. Our results suggest that poloidal flux is a necessary prerequisite for the sustainability of strongly magnetized accretion discs.

7 pages, 3 figures, 1 table; Accepted to MNRAS

References in corpus (7)

• Athena: A New Code for Astrophysical MHD
• Accretion disc viscosity: how big is alpha?
• An Unsplit Godunov Method for Ideal MHD via Constrained Transport in Three Dimensions
• The magnetic nature of disk accretion onto black holes
• Accretion Discs with Strong Toroidal Magnetic Fields
• Thin accretion disks are stabilized by a strong magnetic field
• High accretion rates in magnetised Keplerian discs mediated by a Parker instability driven dynamo

Cited by in corpus (29)

• Large-Scale Poloidal Magnetic Field Dynamo Leads to Powerful Jets in GRMHD Simulations of Black Hole Accretion with Toroidal Field
• Global Radiation Magneto-hydrodynamic Simulations of Sub-Eddington Accretion Disks around Supermassive Black Holes
• Extreme AGN variability: evidence of magnetically elevated accretion?
• Two-Temperature GRRMHD Simulations of M87
• Spontaneous ring formation in wind-emitting accretion discs
• Accretion Geometry in the Hard State of the Black-Hole X-Ray Binary MAXI J1820+070
• Kinetic and radiative power from optically thin accretion flows
• MHD instabilities in accretion disks and their implications in driving fast magnetic reconnection
• Magnetically elevated accretion disks in active galactic nuclei: broad emission line regions and associated star formation
• Magnetized Accretion onto and Feedback from Supermassive Black Holes in Elliptical Galaxies
• The large-scale magnetic field of a thin accretion disk with outflows
• Instability in strongly magnetized accretion discs: A global perspective
• Gravitoturbulent dynamos in astrophysical discs
• The Role of Strong Magnetic Fields in Stabilizing Highly Luminous, Thin Disks
• On the Decay of Strong Magnetization in Global Disc Simulations with Toroidal Fields
• Global Three-Dimensional Radiation Magnetohydrodynamic Simulations of Accretion onto a Stellar Mass Black Hole at Sub- and Near-critical Accretion Rates
• Convective Quenching of Field Reversals in Accretion Disc Dynamos
• HFQPOs and discoseismic mode excitation in eccentric, relativistic discs. II. Magnetohydrodynamic simulations
• The power of the jets accelerated by the coronal magnetic field
• Study of general relativistic magnetohydrodynamic accretion flow around black holes
• Jets in the soft state in Cyg X-3 caused by advection of the donor magnetic field and unification with low-mass X-ray binaries
• HFQPOs and discoseismic mode excitation in eccentric, relativistic discs. I. Hydrodynamic simulations
• Multiphase Circumnuclear Gas in a Low-$\beta$ Disk: Turbulence and Magnetic Field Reversals
• Covering factors of the dusty obscurers in radio-loud and radio-quiet quasars
• Binary black holes in magnetized AGN disks
• Anchoring polar magnetic field in a stationary thick accretion disk
• A 2.5-dimensional viscous, resistive, advective magnetized accretion-outflow coupling in black hole systems: A higher order polynomial approximation. I
• A magnetic accretion disk-outflow model for state transition in X-ray binaries
• Semi-Analytical Model for Wind-Fed Black Hole High-Mass X-ray Binaries -- State Transition Triggered by Magnetic Fields from the Companion Star --