Relaxation Times in Strictly Disk Systems

  • George B. Rybicki
Part of the Astrophysics and Space Science Library book series (ASSL, volume 31)


It is shown that the time of relaxation by particle encounters of self-gravitating systems in the plane interacting by 1/r 2 forces is of the same order of magnitude as the mean orbit time. Therefore such a system does not have a Vlasov limit for large numbers of particles, unless appeal is made to some non-zero thickness of the disk. The relevance of this result to numerical experiments on galactic structure is discussed.


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Copyright information

© D. Reidel Publishing Company, Dordrecht, Holland 1972

Authors and Affiliations

  • George B. Rybicki
    • 1
  1. 1.Smithsonian Astrophysical ObservatoryCambridgeUSA

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