Global 3-D Radiation Magnetohydrodynamic Simulations for FU Ori's Accretion Disk and Observational Signatures of Magnetic Fields

Abstract

FU Ori is the prototype of FU Orionis systems which are outbursting protoplanetary disks. Magnetic fields in FU Ori's accretion disks have previously been detected using spectropolarimetry observations for Zeeman effects. We carry out global radiation ideal MHD simulations to study FU Ori's inner accretion disk. We find that (1) when the disk is threaded by vertical magnetic fields, most accretion occurs in the magnetically dominated atmosphere at z$\sim$R, similar to the "surface accretion" mechanism in previous locally-isothermal MHD simulations. (2) A moderate disk wind is launched in the vertical field simulations with a terminal speed of $\sim$300-500 km/s and a mass loss rate of 1-10\% the disk accretion rate, which is consistent with observations. Disk wind fails to be launched in simulations with net toroidal magnetic fields. (3) The disk photosphere at the unit optical depth can be either in the wind launching region or the accreting surface region. Magnetic fields have drastically different directions and magnitudes between these two regions. Our fiducial model agrees with previous optical Zeeman observations regarding both the field directions and magnitudes. On the other hand, simulations indicate that future Zeeman observations at near-IR wavelengths or towards other FU Orionis systems may reveal very different magnetic field structures. (4) Due to energy loss by the disk wind, the disk photosphere temperature is lower than that predicted by the thin disk theory, and the previously inferred disk accretion rate may be lower than the real accretion rate by a factor of $\sim$2-3.

arXiv comment22 pages, 20 figures, accepted by MNRAS

References in corpus (58)

• Gaia Data Release 2. Summary of the contents and survey properties
• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• Athena: A New Code for Astrophysical MHD
• Using FU Orionis Outbursts to Constrain Self-Regulated Protostellar Disk Models
• Accretion Disks Around Young Objects. III. Grain Growth
• An Unsplit Godunov Method for Ideal MHD via Constrained Transport
• The Burst Mode of Protostellar Accretion
• Episodic accretion in magnetically layered protoplanetary discs
• An Unsplit Godunov Method for Ideal MHD via Constrained Transport in Three Dimensions
• Disk Winds Driven by Magnetorotational Instability and Dispersal of Proto-Planetary Disks
• Non-steady Accretion in Protostars
• Super-Eddington Accretion Disks around Supermassive black Holes
• Vertical Structure of Gas Pressure-Dominated Accretion Disks with Local Dissipation of Turbulence and Radiative Transport
• 2-D simulations of FU Orionis disk outbursts
• Global Evolution of an Accretion Disk with Net Vertical Field: Coronal Accretion, Flux Transport, and Disk Winds
• Transport of Large Scale Poloidal Flux in Black Hole Accretion
• A Near-IR Spectroscopic Survey of FU Orionis Objects
• Global Radiation Magneto-hydrodynamic Simulations of Sub-Eddington Accretion Disks around Supermassive Black Holes
• The Hot Inner Disk of FU Ori
• Direct magnetic field detection in the innermost regions of an accretion disc
• Advection of Magnetic Fields in Accretion Disks: Not So Difficult After All
• The formation of rings and gaps in magnetically coupled disk-wind systems: ambipolar diffusion and reconnection
• High-Resolution Spectroscopy of FUors
• On the Thermal Stability of Radiation Dominated Accretion Disks
• On the Vertical Structure of Radiation-Dominated Accretion Disks
• Accretion Outbursts in Self-gravitating Protoplanetary Disks
• Jets and Outflows From Star to Cloud: Observations Confront Theory
• Episodic Accretion in Young Stars
• A Two-moment Radiation Hydrodynamics Module in Athena Using a Time-explicit Godunov Method
• A systematic survey for eruptive young stellar objects using mid-infrared photometry
• An Algorithm for Radiation Magnetohydrodynamics Based on Solving the Time-dependent Transfer Equation
• Transport of magnetic flux and the vertical structure of accretion discs: I. Uniform diffusion coefficients
• Hall-effect Mediated Magnetic Flux Transport in Protoplanetary Disks
• Strongly magnetized accretion disks: structure and accretion from global magnetohydrodynamic simulations
• Convection Causes Enhanced Magnetic Turbulence in Accretion Disks in Outburst
• Transport of magnetic flux and the vertical structure of accretion discs: II. Vertical profile of the diffusion coefficients
• Gaia 17bpi: An FU Ori Type Outburst
• Radiation Magneto-hydrodynamic Simulations of the Formation of Hot Accretion Disk Coronae
• Flickering in FU Orionis
• Stringent limits on the magnetic field strength in the disc of TW Hya: ALMA observations of CN polarisation
• Radial Transport of Large-Scale Magnetic Fields in Accretion Disks. I. Steady Solutions and an Upper Limit on the Vertical Field Strength
• A Simple Calculation in Service of Constraining the Rate of FU Orionis Outburst Events from Photometric Monitoring Surveys
• Resolving the FU Ori System with ALMA: Interacting Twin Disks?
• A Three-dimensional Simulation of a Magnetized Accretion Disk: Fast Funnel Accretion onto a Weakly Magnetized Star
• Long-wavelength excesses of FU Orionis objects: flared outer disks or infalling envelopes?
• Dead Zones around Young Stellar Objects: FU Orionis Outbursts and Transition Discs
• Accretion in giant planet circumplanetary disks
• The large amplitude outburst of the young star HBC 722 in NGC 7000/IC 5070, a new FU Orionis candidate
• Dynamical Gaseous Rings in Global Simulations of Protoplanetary Disk Formation
• The Periodic Spectroscopic Variability of FU Orionis
• Magnetic Turbulence and Thermodynamics in the Inner Region of Protoplanetary Discs
• Dusty Cloud Acceleration by Radiation Pressure in Rapidly Star-Forming Galaxies
• Are the outflows in FU Orionis systems driven by the stellar magnetic field?
• V346 Normae: First post-outburst observations of an FU Orionis star
• Brightness variations of the FUor-type eruptive star V346 Nor
• Photometric variability in FU Ori and Z CMa as observed by MOST
• Disc wind models for FU Ori objects
• Insights into the inner regions of the FU Orionis disc

Cited by in corpus (36)

• Strongly magnetized accretion disks: structure and accretion from global magnetohydrodynamic simulations
• Magnetic outflows from turbulent accretion disks: I. Vertical structure & secular evolution
• Opacity Driven Convection and Variability in Accretion Disks around Supermassive Black Holes
• Distinguishing between different mechanisms of FU-Orionis-type luminosity outbursts
• Accretion bursts in magnetized gas-dust protoplanetary disks
• Global 3D Radiation Hydrodynamic Simulations of Proto-Jupiter's Convective Envelope
• A two-moment radiation hydrodynamics scheme applicable to simulations of planet formation in circumstellar disks
• Accretion bursts in high-mass protostars: a new testbed for models of episodic accretion
• Application of a Steady-State Accretion Disk Model to Spectrophotometry and High-Resolution Spectra of Two Recent FU Ori Outbursts
• Magnetically-activated accretion outbursts of pre-main sequence discs
• Extreme evaporation of planets in hot thermally unstable protoplanetary discs: the case of FU Ori
• The disk of FU Orionis viewed with MATISSE/VLTI: first interferometric observations in $L$ and $M$ bands
• Modeling the Multiwavelength Evolution of the V960 Mon System
• Time-dependent, long-term hydrodynamic simulations of the inner protoplanetary disk I: The importance of stellar magnetic torques
• Formation of pebbles in (gravito-)viscous protoplanetary disks with various turbulent strengths
• Primordial Dusty Rings and Episodic Outbursts in Protoplanetary Discs
• Episodic accretion and mergers during growth of massive protostars
• Time-dependent, long-term hydrodynamic simulations of the inner protoplanetary disk II: The importance of stellar rotation
• Magnetic disk winds in protoplanetary disks: Description of the model and impact on global disk evolution
• LkH$\alpha$ 225 (V1318 Cyg) South in Outburst
• Eruptive Behavior of Magnetically Layered Protoplanetary Disks in Low Metallicity Environments
• Disk Cooling and Wind Lines As Seen In the Spectral Line Evolution of V960 Mon
• Accretion bursts in young intermediate-mass stars make planet formation challenging
• Disc light variability in the FUor star V646 Puppis as observed by TESS and from the ground
• Multidimensional half-moment multigroup radiative transfer. Improving moment-based thermal models of circumstellar disks
• Time-dependent response of protoplanetary disk temperature to an FU Ori-type luminosity outburst
• MHD in a cylindrical shearing box II: Intermittent Bursts and Substructures in MRI Turbulence
• C/O ratios in self-gravitating protoplanetary discs with dust evolution
• Stellar outbursts and chondrite composition
• Gaia20bdk -- a new FUor in Sh 2-301 Star Forming Region
• Three-dimensional, Time-dependent MHD Simulation of Disk-Magnetosphere-Stellar Wind Interaction in a T Tauri, Protoplanetary System
• Dust in the wind of outbursting young stars
• Tracking the evolution of the accretion flow in MAXI J1820+070 during its hard state with the JED-SAD model
• Modelling the Break in the Specific Angular Momentum within the Envelope-Disk Transition Zone
• Characterizing and spectrally modeling embedded FUor eruptions in the near-infrared
• Evidence of Accretion Burst: The Viscously Heated Inner Disk of the Embedded Protostar IRAS 16316-1540