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Search for the evolutionary relationship between Galactic globular and open clusters using data from the Gaia DR2 Catalog

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 نشر من قبل Anisa Bajkova
 تاريخ النشر 2019
  مجال البحث فيزياء
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Passing through the Galactic disk, a massive object such as a globular cluster, can trigger star formation process leading to the birth of open clusters. Here, we analyze such possible evolutionary relationship between globular and open clusters. To search for the closest rapprochement between objects we computed backwards the orbits of 150 Galactic globular and 232 open clusters (younger than 100 Myr) with proper motions, derived from the Gaia DR2 Catalog. The orbits were computed using the recently modified three-component (disk, bulge and halo) axisymmetric Navarro-Frenk-White potential, which was complemented by non-axisymmetric bar and spiral density wave potentials. We obtained a new estimate for the frequency of impacts of globular clusters about the Galactic disk, which is equal to 4 events for 1 million years. In the framework of the considered scenario, we highlight the following nine pairs of globular and open clusters, with rapprochement within 1 kpc at the time of the intersection the Galactic disk by a globular cluster for the latest 100 Myr: NGC 104 - Turner 3, NGC 104 - NGC 6396, NGC 104 - Ruprecht 127, NGC 5139 - Trumpler 17, NGC 5139 - NGC 6520, NGC 6341 - NGC 6613, NGC 6838 - NGC 6520, NGC 7078 - NGC 7063, NGC 6760 - Ruprecht 127.


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