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Search for New Open Clusters in Huge Catalogues

Ivan Zolotukhin·Sergey Koposov·Elena Glushkova
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Abstract

Current catalogues of open clusters are rather heterogeneous and incomplete lists of clusters than true catalogues. Before there has been no attempts of automatic search for open clusters in huge photometric catalogues using homogeneous all-sky approach. We have developed such a method based on extraction from catalogue and successive analysis of stellar densities using the colour-magnitude diagrams. Our algorithm finds density peaks and then verifies the significance of these peaks exploiting the fact that in real clusters only stars lying on the isochrone must show density peaks, in contrast with stars lying far from the isochrone on the CMD. In addition such procedure allows to determine the physical parameters: age, distance and color excess of open clusters. Preliminary study of 150 sq. degrees in Galaxy anticenter region yielded several dozens of new clusters. The software developed will allow to build first homogeneous all-sky open cluster catalogue (it will include essentially refined data for known clusters as well) based on 2MASS data.

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Ivan Zolotukhin, Sergey Koposov, Elena Glushkova. 2006-01-30. Search for New Open Clusters in Huge Catalogues. https://arxiv.org/abs/astro-ph/0601691

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