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تسجيل مستخدم جديدBOAO Photometric Survey of Galactic Open Clusters. III. Czernik 24 and Czernik 27
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تأليف
Sang Chul Kim
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We present BV CCD photometry for the open clusters Czernik 24 and Czernik 27. These clusters have never been studied before, and we provide, for the first time, the cluster parameters; reddening, distance, metallicity and age. Czernik 24 is an old open cluster with age 1.8 +/- 0.2 Gyr, metallicity [Fe/H]=-0.41 +/- 0.15 dex, distance modulus (m-M)_0 = 13.1 +/- 0.3 mag (d=4.1 +/- 0.5 kpc), and reddening E(B-V) = 0.54 +/- 0.12 mag. The parameters for Czernik 27 are estimated to be age = 0.63 +/- 0.07 Gyr, [Fe/H]= -0.02 +/- 0.10 dex, (m-M)_0 = 13.8 +/- 0.2 mag (d=5.8 +/- 0.5 kpc), and E(B-V) = 0.15 +/- 0.05 mag. The metallicity and distance values for Czernik 24 are consistent with the relation between the metallicity and the Galactocentric distance of other old open clusters. We find the metallicity gradient of 51 old open clusters including Czernik 24 to be Delta [Fe/H]/Delta R_gc= -0.064 +/- 0.009 dex/kpc.
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