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What do dynamical cluster masses really tell us about dynamics?

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 نشر من قبل Richard de Grijs
 تاريخ النشر 2008
  مجال البحث فيزياء
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 تأليف Richard de Grijs




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The diagnostic age versus mass-to-light ratio diagram is often used in attempts to constrain the shape of the stellar initial mass function, and the stability and the potential longevity of extragalactic young to intermediate-age massive star clusters. Here, we explore the pitfalls associated with this approach and its potential for use with Galactic open clusters. We conclude that for an open cluster to survive for any significant fraction of a Hubble time (in the absence of substantial external perturbations), it is a necessary but not a sufficient condition to be located close to the predicted photometric evolutionary sequences for normal simple stellar populations.



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