Three-dimensional Simulations of Magnetospheric Accretion in a T Tauri Star: Accretion and Wind Structures Just Around Star

Abstract

We perform three-dimensional magnetohydrodynamic simulations of magnetospheric accretion in a T Tauri star to study the accretion and wind structures in the close vicinity of the star. The gas accreting onto the star consists of the gas from the magnetospheric boundary and the failed disk winds. The accreting gas is commonly found as a multi-column accretion, which is consistent with observations. A significant fraction of the angular momentum of the accreting flows is removed by the magnetic fields of conical disk winds and turbulent failed winds inside and near the magnetosphere. As a result, the accretion torque is significantly reduced compared to the simple estimation based on the mass accretion rate. The stellar spin affects the time variability of the conical disk wind by changing the stability condition of the magnetospheric boundary. However, the time-averaged magnetospheric radius only weakly depends on the stellar spin, which is unlike the prediction of classical theories that the stellar spin controls the magnetospheric radius through the magnetic torque. The ratio of the toroidal to the poloidal field strengths at the magnetospheric boundary, which is a key parameter for the magnetic torque, is also insensitive to the spin; it is rather determined by the disk dynamics. Considering newly found three-dimensional effects, we obtain a scaling relation of the magnetospheric radius very similar to the Ghosh & Lamb relation from the steady angular momentum transport equation.

38 pages, 21 figures. Accepted for publication in ApJ

References in corpus (22)

• The Athena++ Adaptive Mesh Refinement Framework: Design and Magnetohydrodynamic Solvers
• Magnetospheric accretion-ejection processes in the classical T Tauri star AA
• Evolution of Protoplanetary Discs with Magnetically Driven Disc Winds
• Accretion to Magnetized Stars through the Rayleigh-Taylor Instability: Global Three-Dimensional Simulations
• "Propeller" Regime of Disk Accretion to Rapidly Rotating Stars
• Accretion funnels onto weakly magnetized young stars
• CSI 2264: Probing the inner disks of AA Tau-like systems in NGC 2264
• Above-the-loop-top Oscillation and Quasi-periodic Coronal Wave Generation in Solar Flares
• Turbulence-driven Polar Winds from T Tauri Stars Energized by Magnetospheric Accretion
• Warps, bending and density waves excited by rotating magnetized stars: results of global 3D MHD simulations
• Estimating magnetic filling factors from Zeeman-Doppler magnetograms
• X-Ray flares in Orion Young Stars. II. Flares, Magnetospheres, and Protoplanetary Disks
• General-Relativistic Simulations of Four States of Accretion onto Millisecond Pulsars
• Magnetic outflows from turbulent accretion disks: I. Vertical structure & secular evolution
• X-ray Super-Flares From Pre-Main Sequence Stars: Flare Energetics And Frequency
• Multi-epoch Ultraviolet HST Observations of Accreting Low-mass Stars
• A measure of the size of the magnetospheric accretion region in TW Hydrae
• Alfvén-wave driven magnetic rotator winds from low-mass stars I: rotation dependences of magnetic braking and mass-loss rate
• Magnetic braking of accreting T Tauri stars: Effects of mass accretion rate, rotation, and dipolar field strength
• The ODYSSEUS Survey. Motivation and First Results: Accretion, Ejection, and Disk Irradiation of CVSO 109
• Giant protostellar flares: accretion-driven accumulation and reconnection-driven ejection of magnetic flux in protostars
• Slingshot prominences: a hidden mass loss mechanism

Cited by in corpus (13)

• Magnetically Arrested Circumbinary Accretion Flows
• Evidence for Variable Accretion onto PDS 70 c and Implications for Protoplanet Detections
• Constraints on PDS 70 b and c from the dust continuum emission of the circumplanetary discs considering in situ dust evolution
• Modeling of Thermal Emission from ULX Pulsar Swift J0243.6+6124 with General Relativistic Radiation MHD simulations
• Global 3-D Simulations of Magnetospheric Accretion: II. Hot Spots, Equilibrium Torque, Episodic Wind, and Midplane Outflow
• GR-RMHD Simulations of Super-Eddington Accretion Flows onto a Neutron Star with Dipole and Quadrupole Magnetic Fields
• Photoevaporation Can Reproduce Extended ${\mathrm{H}}_2$ Emission from Protoplanetary Disks Imaged by JWST MIRI
• The High-resolution Accretion Disks of Embedded protoStars (HADES) simulations. I. Impact of Protostellar Magnetic Fields on the Accretion Modes
• On the diversification and dissipation of protoplanetary disks
• Three-dimensional, Time-dependent MHD Simulation of Disk-Magnetosphere-Stellar Wind Interaction in a T Tauri, Protoplanetary System
• Long-term evolution of the temperature structure in magnetized protoplanetary disks and its implication for the dichotomy of planetary composition
• Oxygen Isotope Exchange Between Molten Silicate Spherules and Ambient Water Vapor with Nonzero Relative Velocity: Implication for Chondrule Formation Environment
• The azimuthal structure of magnetically arrested disks during flux eruption events