2000/07/22 by Douglas C. Heggie, Heggie, Douglas C.
Earth and Planetary Sciences · Physics and Astronomy · #Astro and Planetary Science #Astrophysics (astro-ph) #FOS: Physical sciences #Geophysics and Gravity Measurements #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0007336
12 pages, 6 figures; to appear in Dynamics of Star Clusters and the Milky Way, eds S. Deiters, B. Fuchs, A. Just, R. Spurzem, R. Wielen; ASP Conf. Ser
arxiv created 2000/07/22 · openalex publication_date 2000/07/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider both observational and theoretical issues related to dynamical mass loss from the old globular star clusters of the Galaxy. On the observational side the evidence includes tidal tails and extratidal extensions, kinematic effects, effects on the mass function, and influences on the statistical properties of surviving objects. Even for isolated clusters, the theoretical issues are not fully understood. The effects of a steady tide (i.e. for a cluster in a circular orbit) include the imposition of a tidal boundary, and lowering of the escape energy. Less familiar, however, are the effects of induced mass loss. Even the definition of an ``escaper'' is not straightforward. When mass loss is driven by relaxation, as in N-body models, the rate of loss of mass does not scale in a simple way with the relaxation time. Reasons for this include the very long time scales on which stars escape even with energies above the escape threshold. For the realistic case of unsteady tides it is still unclear under what circumstances mass loss is dominated by relaxation or tidal heating.