The stability of accretion tori. II - Non-linear evolution to discrete planets
Abstract
Hawley has shown through two-dimensional computer simulations that a slender torus in which a linear Papaloizou-Pringle (PP) instability with azimuthal wavenumber m, is excited evolves non-linearly to a configuration with m nearly disconnected "planets". The authors present an analytical fluid equilibrium that they believe represents his numerical planets. They analyse the linear modes of the analytical planet and find that there are numerous instabilities, though they are not as violent as the PP instability in the torus. The authors also discuss the energy and vorticity of neutral modes, and they argue that when the torus breaks up into planets, neutral modes with negative energy and non-zero vorticity are excited in order to conserve total energy and specific vorticity. The authors speculate that the fluid in Hawley's simulations may be approaching two-dimensional turbulence.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 1987
- DOI:
- 10.1093/mnras/225.3.695
- Bibcode:
- 1987MNRAS.225..695G
- Keywords:
-
- Accretion Disks;
- Astronomical Models;
- Magnetohydrodynamic Stability;
- Nonlinear Evolution Equations;
- Planetary Evolution;
- Toroidal Plasmas;
- Coriolis Effect;
- Equilibrium Flow;
- Two Dimensional Flow;
- PLANETS;
- FORMATION;
- ACCRETION;
- EVOLUTION;
- COMPUTER METHODS;
- SIMULATIONS;
- TORUS;
- STABILITY;
- MOTION;
- HYDRODYNAMICS;
- EQUILIBRIUM;
- ENERGY;
- FLUIDS;
- TURBULENCE;
- CALCULATIONS;
- MODELS;
- Astrophysics; Planets