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A proper motion study of the globular clusters M4, M12, M22, NGC 3201, NGC 6362 and NGC 6752

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 نشر من قبل Michal Rozyczka
 تاريخ النشر 2013
  مجال البحث فيزياء
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We derive relative proper motions of stars in the fields of globular clusters M4, M12, M22, NGC 3201, NGC 6362 and NGC 6752 based on a uniform data set collected between 1997 and 2008. We assign a membership class for each star with a measured proper motion, and show that these membership classes can be successfully used to eliminate field stars from color-magnitude diagrams of the clusters. They also allow for the efficient selection of rare objects such as blue/yellow/red stragglers and stars from the asymptotic giant branch. Tables with proper motions and photometry of over 87000 stars are made publicly available via the Internet.



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