CCD ubvy photometry of the bimodal main-sequence cluster NGC 3680

Journal Article · Wed Nov 01 04:00:00 EST 1989 · Astronomical Journal; (USA)

DOI:https://doi.org/10.1086/115247· OSTI ID:7253697

Anthony-Twarog, B J; Twarog, B A; Shodhan, S ^[1]

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1. Kansas Univ., Lawrence (USA)

CCD uvby photometry for the intermediate age, southern open cluster, NGC 3680, is analyzed. For a reddening of E(b-y) = 0.034, a true cluster modulus of 9.74 + or - 0.20 and a cluster metallicity of Fe/H abundance = 0.10 + or - 0.09, based on 18 probable nonbinary members of the cluster brighter than V = 14. The color-magnitude diagram for the cluster suggests that, although the main sequence may be subject to the same bimodal distibution as NGC 752, the likely source in both clusters is a combination of binaries and a sharply curved turnoff. The color-magnitude diagram is compared to the theoretical isochrones of Bertelli et al. (1988), showing an age of (1.9 + or - 0.3) X 10 to the 9th yr. 27 refs.

• OSTI ID: 7253697
• Journal Information: Astronomical Journal; (USA), Journal Name: Astronomical Journal; (USA) Vol. 98; 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
ABUNDANCE
AGE ESTIMATION
CHARGE-COUPLED DEVICES
CHEMICAL COMPOSITION
COMPARATIVE EVALUATIONS
ELEMENT ABUNDANCE
ELEMENTS
HYDROGEN
IRON
MAIN SEQUENCE STARS
METALS
NONMETALS
PHOTOMETRY
SEMICONDUCTOR DEVICES
STAR CLUSTERS
STARS
TRANSITION ELEMENTS