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X-Ray Binaries and the Dynamical States of Globular Clusters

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 نشر من قبل John M. Fregeau
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف John M. Fregeau




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We summarize and discuss recent work (Fregeau 2007) that presents the confluence of three results suggesting that most Galactic globular clusters are still in the process of core contraction, and have not yet reached the thermal equilibrium phase driven by binary scattering interactions: that 1) the three clusters that appear to be overabundant in X-ray binaries per unit encounter frequency are observationally classified as core-collapsed, 2) recent numerical simulations of cluster evolution with primordial binaries show that structural parameters of clusters in the binary-burning phase agree only with core-collapsed clusters, and 3) a cluster in the binary-burning phase for the last few Gyr should have about 5 times more dynamically formed X-ray sources than if it were in the core contraction phase for the same time.



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177 - John M. Fregeau 2007
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