The lifetimes of spiral patterns in disc galaxies

  title={The lifetimes of spiral patterns in disc galaxies},
  author={J. A. Sellwood},
  journal={Monthly Notices of the Royal Astronomical Society},
  • J. Sellwood
  • Published 16 August 2010
  • Physics
  • Monthly Notices of the Royal Astronomical Society
The rate of internally driven evolution of galaxy discs is strongly affected by the lifetimes of the spiral patterns they support. Evolution is much faster if the spiral patterns are recurrent short-lived transients rather than long-lived, quasi-steady features. As rival theories are still advocated based on these two distinct hypotheses, I review the evidence that bears on the question of the lifetimes of spiral patterns in galaxies. Observational evidence from external galaxies is… 

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