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arXiv · 1005.2237

Effects of Hardness of Primordial Binaries on Evolution of Star Clusters

Ataru Tanikawa·Toshiyuki Fukushige
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Abstract

We investigate effects of hardness of primordial binaries on whole evolution of star clusters by means of N-body simulations. Using newly developed code, GORILLA, we simulated eleven N=16384 clusters with primordial binaries whose binding energies are equal in each cluster in range of 1-300kT_0, where 1.5kT_0 is average stellar kinetic energy at the initial time. We found that, in both soft (< 3kT_0) and hard (> 300kT_0) limits, clusters experience deep core collapse. In the intermediate hardness (10-100kT_0), the core collapses halt halfway due to an energy releases of the primordial binaries. The core radii at the halt can be explained by their energy

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Ataru Tanikawa, Toshiyuki Fukushige. 2010-05-13. Effects of Hardness of Primordial Binaries on Evolution of Star Clusters. https://doi.org/10.1093/pasj%2F61.4.721

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