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arXiv · 0911.4382

The Progeny of Stellar Dynamics and Stellar Evolution within an N-body model of NGC 188

A. M. Geller·J. R. Hurley·R. D. Mathieu
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Abstract

We present a direct N-body simulation modeling the evolution of the old (7 Gyr) open cluster NGC 188. This is the first N-body open cluster simulation whose initial binary population is directly defined by observations of a specific open cluster: M35 (150 Myr). We compare the simulated color-magnitude diagram at 7 Gyr to that of NGC 188, and discuss the blue stragglers produced in the simulation. We compare the solar-type main sequence binary period and eccentricity distributions of the simulation to detailed observations of similar binaries in NGC 188. These results demonstrate the importance of detailed observations in guiding N-body open cluster simulations. Finally, we discuss the implications of a few discrepancies between the NGC 188 model and observations and suggest a few methods for bringing N-body open cluster simulations into better agreement with observations.

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A. M. Geller, J. R. Hurley, R. D. Mathieu. 2009-11-23. The Progeny of Stellar Dynamics and Stellar Evolution within an N-body model of NGC 188. https://doi.org/10.1017/s1743921309991128

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