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arXiv · astro-ph/0508550

Photometry of neglected open clusters in the First and Fourth Galactic Quadrants

Abstract

CCD $BVI$ photometry is presented for 8 previously unstudied star clusters located in the First and Fourth Galactic Quadrants: AL~1, BH 150, NGC 5764, Lynga~9, Czernik~37, BH 261, Berkeley~80 and King~25. Color magnitude diagrams of the cluster regions suggest that several of them (BH 150, Lynga~9, Czernik~37 and BH 261 and King~25) are so embedded in the dense stellar population toward the galactic center that their properties, or even their existence as physical systems, cannot be confirmed. Lynga~9, BH 261 and King~25 appear to be slight enhancements of dense star fields, BH 150 is probably just a single bright star in a dense field, and Czernik~37 may be a sparse, but real cluster superimposed on the galactic bulge population. We derive preliminary estimates of the physical parameters for the remaining clusters. AL~1 appears to be an intermediate age cluster beyond the solar circle on the far side of the galaxy and the final two clusters, NGC 5764 and Berkeley 80 are also of intermediate age but located inside the solar ring. This set of clusters highlights the difficulties inherent in studying the stellar populations toward the inner regions of the galaxy.

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Giovanni Carraro, Kenneth A. Janes, Jason D. Eastman. 2005-08-25. Photometry of neglected open clusters in the First and Fourth Galactic Quadrants. https://doi.org/10.1111/j.1365-2966.2005.09551.x

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