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Final Stages of N-body Star Cluster Encounters

M. R. de Oliveira·E. Bica·H. Dottori
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Abstract

We performed numerical simulations of star cluster encounters with Hernquist's TREECODE in a CRAY YMP-2E computer. We used different initial conditions (relative positions and velocities, cluster sizes, masses and concentration degrees) with total number of particles per simulation ranging from 4608 to 20480. Long term interaction stages (up to 1 Gyr) when the pair coalesces into a single cluster are compared with isolated LMC clusters. Evidence is found that when seen in a favourable plane these resulting clusters show elliptical shapes due to the disruption of one of the companions. These elliptical shapes are essentially time independent but they do depend on the initial structural parameters of the pair components. We also analyzed the fraction of stars that are ejected to the field by the interaction. We found that this fraction can be almost 50% for the disrupted cluster. These simulations can represent a possible mechanism to explain the ellipticity observed on several star clusters in the Magellanic Clouds.

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M. R. de Oliveira, E. Bica, H. Dottori. 1999-10-11. Final Stages of N-body Star Cluster Encounters. https://doi.org/10.1046/j.1365-8711.2000.03093.x

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