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تسجيل مستخدم جديدCCD UBV(RI)KC Photometry of the Open Clusters Juchert 9 and Berkeley 97
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The CCD UBV(RI)KC photometry of the poorly studied open clusters Juchert 9 (Juc 9) and Berkeley 97 (Be 97), which are observed with the 0.84 m telescope at the San Pedro Martir National Observatory, Mexico has been analysed. For the likely cluster members, we determined the reddenings, E(B-V)=0.82 +- 0.04 (Juc 9) and E(B-V)=0.87 +- 0.05 (Be 97), from the early type stars. Our distance moduli/distances for only (B - V) colour are (Vo-Mv , d(kpc)) = (13.40 +- 0.10, 4.8 +- 0.2 kpc) (Juc 9) and (12.40 +- 0.12, 3.0 +- 0.2 kpc) (Be 97), respectively. The Gaia DR2 distances are d = 4.5 +- 1.2 kpc (Juc 9) and d = 3.1 +- 0.7 kpc (Be 97) from the median parallaxes with relative parallaxes < 0.20, which are in good agreement with the photometric distances within the uncertainties. The solar abundance PARSEC isochrones give us the intermediate ages, 30 +- 10 Myr for Juc 9 and 100 +- 30 Myr for Be 97.
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