UBV CCD PHOTOMETRY OF THE INTERMEDIATE AGE OPEN CLUSTER NGC 6716

  • CHUN MOO-YOUNG (Bohyunsan Optical Astronomy Observatory, Korea Astronomy Observatory) ;
  • LEE SEE-WOO (Department of Astronomy, Seoul National University)
  • Published : 1996.10.01

Abstract

NGC 6716 is an intermediate-age open cluster in Sagittarius. In this paper, we present the new UBV CCD photometry of the stars in the cluster, which is deeper than previous ones. From the color-color diagram and the color-magnitude diagram, we derived a reddening $E_{B- V} = 0.17\pm0.03$ and a distance modulus of the cluster, $(V - Mv)_o = 9.2\pm0.1$. An age of the cluster is estimated as $8\pm10^7 yrs$ from the latest isochrone. Luminosity function and mass function of the cluster are derived. The gradient of the mass function of bright stars is a bit steep, $\Gamma = -1.85\pm0.05$, and there is no distinct bump and dip in the mass function.

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