We present a new UBVI CCD photometry of the intermediate-age open cluster NGC 2420. Our photometry covers a field of 7′9×7.′7 7′9×7.′7 of the sky centered on the cluster. We determined the reddening and distance to the cluster by the main sequence fitting as E(B−V)=0.05±0.02 E(B−V)=0.05±0.02 and (m−M)o=11.9±0.1 (m−M)o=11.9±0.1 , along with the age of \~2 \~2 Gyr by fitting the Padova isochrones to the observed color-magnitude diagrams of the cluster. The fraction of binaries is found to be 44±5% 44±5% and they are likely to locate in the central region of the cluster. The spatial distributions of the binaries and the variation of the cluster luminosity functions along the radius suggest mass segregations due to the dynamical evolution of the cluster.

• 이상현(부산대학교 지구과학과) | LEE SANG HYUN (Department of Earth Sciences, Pusan National University)
• 안홍배(부산대학교 지구과학과) | ANN HONG BAE (Department of Earth Sciences, Pusan National University)
• 강용우(부산대학교 지구과학과) | KANG YONG-WOO (Department of Earth Sciences, Pusan National University)