The local axisymmetric instability criterion in a thin, rotating, multicomponent disc

  title={The local axisymmetric instability criterion in a thin, rotating, multicomponent disc},
  author={Roman R. Rafikov},
  journal={Monthly Notices of the Royal Astronomical Society},
  • R. Rafikov
  • Published 5 July 2000
  • Physics
  • Monthly Notices of the Royal Astronomical Society
Purely gravitational perturbations are considered in a thin rotating disc composed of gas and several stellar components. The dispersion relation for the axisymmetric density waves propagating through the disc is found and the criterion for the local axisymmetric stability of the whole system is formulated. In the appropriate limit of two-component gas we confirm the findings of Jog & Solomon and extend consideration to the case when one component is collisionless. Gravitational stability of… 

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