Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-08-25
Mon.Not.Roy.Astron.Soc.392:969-981,2009
Astronomy and Astrophysics
Astrophysics
14 pages, 17 figures; accepted by MNRAS
Scientific paper
10.1111/j.1365-2966.2008.14099.x
Tidal tails of star clusters are not homogeneous but show well defined clumps in observations as well as in numerical simulations. Recently an epicyclic theory for the formation of these clumps was presented. A quantitative analysis was still missing. We present a quantitative derivation of the angular momentum and energy distribution of escaping stars from a star cluster in the tidal field of the Milky Way and derive the connection to the position and width of the clumps. For the numerical realization we use star-by-star $N$-body simulations. We find a very good agreement of theory and models. We show that the radial offset of the tidal arms scales with the tidal radius, which is a function of cluster mass and the rotation curve at the cluster orbit. The mean radial offset is 2.77 times the tidal radius in the outer disc. Near the Galactic centre the circumstances are more complicated, but to lowest order the theory still applies. We have also measured the Jacobi energy distribution of bound stars and showed that there is a large fraction of stars (about 35%) above the critical Jacobi energy at all times, which can potentially leave the cluster. This is a hint that the mass loss is dominated by a self-regulating process of increasing Jacobi energy due to the weakening of the potential well of the star cluster, which is induced by the mass loss itself.
Berczik Peter
Ernst Arthur
Just Andreas
Petrov M. I.
No associations
LandOfFree
Quantitative analysis of clumps in the tidal tails of star clusters does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Quantitative analysis of clumps in the tidal tails of star clusters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantitative analysis of clumps in the tidal tails of star clusters will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-380291