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Core-Collapse Times of Two-Component Clusters

Sungsoo S. Kim·Hyung Mok Lee
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Abstract

We examine the corecollapse times of isolated, two-mass-component star clusters using Fokker-Planck models. With initial condition of Plummer models, we find that the corecollapse times of clusters with M_1/M_2 >> 1 are well correlated with (N_1/N_2)^{1/2}(m_1/m_2)^{2} t_{rh}, where M_1/M_2 and m_1/m_2 are the light to heavy component total and individual mass ratios, respectively, N_1/N_2 is the number ratio, and t_{rh} is the initial half-mass relaxation time scale. We also find two-component cluster parameters that best match multi-component (thus more realistic) clusters with power-law mass functions.

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Sungsoo S. Kim, Hyung Mok Lee. 1997-11-11. Core-Collapse Times of Two-Component Clusters. https://arxiv.org/abs/astro-ph/9711109

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