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UBVI photometry of the intermediate age open cluster NGC 6939

Gloria Andreuzzi·Angela Bragaglia·Monica Tosi·Gianni Marconi
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Abstract

We present CCD UBVI photometry of the nearby, intermediate age open cluster NGC 6939. Using the synthetic Colour - Magnitude Diagrams technique we estimate the following parameters: age between 1.3 and 1.0 Gyr (depending on whether or not overshooting is considered), reddening 0.34<E(B-V)<0.38 and distance modulus 11.3<mod_0<11.4 .

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Gloria Andreuzzi, Angela Bragaglia, Monica Tosi, Gianni Marconi. 2003-11-13. UBVI photometry of the intermediate age open cluster NGC 6939. https://doi.org/10.1111/j.1365-2966.2004.07366.x

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