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Formation and evolution of clumpy tidal tails around globular clusters

R. Capuzzo Dolcetta·P. Di Matteo·P. Miocchi
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Abstract

We present some results of numerical simulations of a globular cluster orbiting in the central region of a triaxial galaxy on a set of 'loop' orbits. Tails start forming after about a quarter of the globular cluster orbital period and develop, in most cases, along the cluster orbit, showing clumpy substructures as observed, for example, in Palomar 5. If completely detectable, clumps can contain about 7,000 solar masses each, i.e. about 10% of the cluster mass at that epoch. The morphology of tails and clumps and the kinematical properties of stars in the tails are studied and compared with available observational data. Our finding is that the stellar velocity dispersion tends to level off at large radii, in agreement to that found for M15 and Omega Centauri.

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R. Capuzzo Dolcetta, P. Di Matteo, P. Miocchi. 2004-06-14. Formation and evolution of clumpy tidal tails around globular clusters. https://doi.org/10.1086/426006

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