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arXiv · astro-ph/9608167

UBVRI CCD photometry of the old open cluster NGC 6253

A. Bragaglia·G. Tessicini·M. Tosi·G. Marconi·U. Munari
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Abstract

We present UBVRI photometry for the old open cluster NGC 6253. From comparison of the observed colour-magnitude diagrams with simulations based on stellar evolutionary models we derive in a self consistent way reddening, distance, and age of the cluster: E(B-V) = 0.23-0.32, (m-M)$_0$ = 10.9$\pm$0.1, metallicity roughly double than solar, and age $\simeq$ 3 Gyr. The cluster has a binary sequence, discernible even through the field contamination, suggesting that about 1/3 of the cluster members belong to binary, or multiple, systems.

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A. Bragaglia, G. Tessicini, M. Tosi, G. Marconi, U. Munari. 1996-08-27. UBVRI CCD photometry of the old open cluster NGC 6253. https://doi.org/10.1093/mnras%2F284.2.477

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