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Updated: Jun 5, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
High-growth-rate magnetohydrodynamic instability in differentially rotating compressible flow
1Theoretical Astrophysics Section, Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085, India. mradul@barc.gov.in
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
Turbulence in accretion disks, driven by instabilities, transports angular momentum outward, enabling accretion. A new high-growth instability emerges when magnetic energy surpasses rotational energy in magnetized flows.
Area of Science:
- Astrophysics
- Plasma Physics
- Fluid Dynamics
Background:
- Accretion disks require outward angular momentum transport for matter to accrete.
- Turbulence is a key mechanism for achieving this transport.
- Instabilities are a primary source of turbulence in astrophysical flows.
Purpose of the Study:
- To investigate the role of instabilities in generating turbulence within accretion disks.
- To identify and characterize novel instabilities in magnetized, differentially rotating flows.
- To determine the conditions under which these instabilities occur.
Main Methods:
- Numerical simulations of differentially rotating compressive flows.
- Inclusion of non-vanishing radial and azimuthal magnetic fields.
- Analysis of flow dynamics and instability growth rates.
Main Results:
- Demonstration of a high growth rate instability in the studied flow.
- Identification of the instability's operational regime.
- The instability thrives where magnetic energy density exceeds rotational energy density.
Conclusions:
- A specific type of instability can drive turbulence in magnetized accretion disks.
- This instability is significant in regions with strong magnetic fields relative to rotation.
- Understanding such instabilities is crucial for models of accretion processes.
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