Magnetorotational Instability in Diamagnetic, Misaligned Protostellar Discs
arXiv:2002.02254 · doi:10.1093/mnras/stz3358
Abstract
In the present study, we addressed the question of how the growth rate of the magnetorotational instability is modified when the radial component of the stellar dipole magnetic field is taken into account in addition to the vertical component. Considering a fiducial radius in the disc where diamagnetic currents are pronounced, we carried out a linear stability analysis to obtain the growth rates of the magnetorotational instability for various parameters such as the ratio of the radial-to-vertical component and the gradient of the magnetic field, the Alfvenic Mach number and the diamagnetization parameter. Our results show that the interaction between the diamagnetic current and the radial component of the magnetic field increases the growth rate of the magnetorotational instability and generates a force perpendicular to the disc plane which may induce a torque. It is also shown that considering the radial component of the magnetic field and taking into account a radial gradient in the vertical component of the magnetic field causes an increase in the magnitudes of the growth rates of both the axisymmetric () and the non-axisymmetric () modes.
arXiv comment9 pages, 5 figures, published in MNRAS, 2020, vol. 491, pages 5481-5488
References in corpus (21)
- Dynamics of Protoplanetary Disks
- Linear Analysis of the Hall Effect in Protostellar Disks
- Thanatology in Protoplanetary Discs: the combined influence of Ohmic, Hall, and ambipolar diffusion on dead zones
- Magnetospheric accretion-ejection processes in the classical T Tauri star AA
- Evolution of Spin Direction of Accreting Magnetic Protostars and Spin-Orbit Misalignment in Exoplanetary Systems
- Hall-effect Controlled Gas Dynamics in Protoplanetary Disks: II. Full 3D Simulations toward the Outer Disk
- Magnetorotational Instability Driven Accretion in Protoplanetary Disks
- Magnetically driven accretion in protoplanetary discs
- Magnetically Driven Warping, Precession and Resonances in Accretion Disks
- Magnetic self-organisation in Hall-dominated magnetorotational turbulence
- Signatures of broken protoplanetary discs in scattered light and in sub-millimetre observations
- On the Linear Stability of Weakly-Ionized, Magnetized Planar Shear Flows
- The Stability of Magnetized Rotating Plasmas with Superthermal Fields
- Shadows and asymmetries in the T Tauri disk HD 143006: Evidence for a misaligned inner disk
- Magnetohydrodynamic Instabilities in Shearing, Rotating, Stratified Winds and Disks
- Evolution of Spin Direction of Accreting Magnetic Protostars and Spin-Orbit Misalignment in Exoplanetary Systems: II. Warped Discs
- Kinematics of the CO Gas in the Inner Regions of the TW Hya Disk
- Warping of Accretion Disks with Magnetically Driven Outflows: A Possible Origin for Jet Precession
- An Ordered Magnetic Field in the Protoplanetary Disk of AB Aur Revealed by Mid-Infrared Polarimetry
- A local model of warped magnetised accretion discs
- Magnetic field gradient effects on the magnetorotational instability