Coherent Stellar Motion in Galactic Spiral Arms by Swing Amplification

  title={Coherent Stellar Motion in Galactic Spiral Arms by Swing Amplification},
  author={S. Michikoshi and E. Kokubo},
  journal={arXiv: Astrophysics of Galaxies},
We perform local $N$-body simulations of disk galaxies and investigate the evolution of spiral arms. We calculate the time autocorrelation of the surface density of spiral arms and find that the typical evolution timescale is described by the epicycle period. We investigate the distribution of the orbital elements of stars and find that in spiral arms the epicycle motions of stars are in phase while the spatial distribution of the guiding center is nearly uniform. These facts clearly show that… Expand
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Spiral instabilities: linear and non-linear effects


Galactic Dynamics (2nd ed.; Princeton, NJ
  • 2008