A CCD photometric analysis of the old open cluster NGC 2420

Journal Article · Tue May 01 04:00:00 EDT 1990 · Astronomical Journal; (USA)

DOI:https://doi.org/10.1086/115436· OSTI ID:6690946

Anthony-Twarog, B J; Twarog, B A; Kaluzny, J; Shara, M M ^[1]

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1. Kansas Univ., Lawrence (USA) Obserwatorium Astronomiczne, Warsaw (Poland) Space Telescope Science Institute, Baltimore, MD (USA)

Precision CCD photometry on the BV system of the core of the old open cluster NGC 2420 is analyzed to explore the value of such an approach for open clusters, particularly in the areas of Galactic and stellar evolution. The unevolved main sequence is shown to be narrow and well defined to the completeness limit of V = 18.5, and the distribution of stars away from the main sequence is shown to be bimodal, with a secondary peak located approximately 0.7 mag above the fiducial main sequence. It is estimated that 50 percent of the cluster systems are binary. Near the turnoff the cluster exhibits some detailed structure. Fiducial relations are given for the cluster extending from the lower main sequence to the red giant branch 1.5 mag above the clump. Comparisons are made between the NGC 2420 cluster and NGC 2506, the isochrones of VandenBerg (1985), and 47 Tuc, in order to estimate cluster parameters, including reddening and metallicity. 68 refs.

• OSTI ID: 6690946
• Journal Information: Astronomical Journal; (USA), Journal Name: Astronomical Journal; (USA) Vol. 99; ISSN 0004-6256; ISSN ANJOA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABSORPTION
ABUNDANCE
BINARY STARS
CHARGE-COUPLED DEVICES
ELEMENT ABUNDANCE
GALAXIES
GIANT STARS
INTERSTELLAR SPACE
MAIN SEQUENCE STARS
MILKY WAY
RED GIANT STARS
SEMICONDUCTOR DEVICES
SPACE
SPECTROPHOTOMETRY
STAR CLUSTERS
STAR EVOLUTION
STARS