NGC 1868: A metal-poor intermediate-age cluster in the large Magellanic cloud

Journal Article · Fri Feb 01 04:00:00 EST 1980 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/157680· OSTI ID:5364189

Flower, P J; Geisler, D; Hodge, P; Olszewski, E W

NGC 1868 is a rich, blue globular-like cluster in the LMC, located sufficiently far from the main body of the Cloud to allow accurate faint photometry of its stars. Its C-M diagram shows a well-populated main sequence with a turnoff at M/sub v/approx. ==+0.4. The well-populated giant branch is much too blue to fit models with solar metals abundance. It has its faint red giant at B-V=+0.70, M/sub v/=+1.0, and a blue loop at M/sub v/=0.0 extending to B-V=+0.50. The brightest red giants reach M/sub v/approx.-0.5 and B-V=1.15. The best fit of the giant branch is with a Z of 0.001, a turnoff mass of 2.0 M/sub sun/, and an age of 7 x 10/sup 8/ years. Ten anomalously bright giants are found near the center of the cluster, and several hypotheses are suggested to explain them.

• Research Organization: Clemson University
• OSTI ID: 5364189
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 235:3; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
GALAXIES
GIANT STARS
MAGELLANIC CLOUDS
MATHEMATICAL MODELS
PHOTOMETRY
STAR CLUSTERS
STAR MODELS
STARS