Washington CCD photometry of the disk globular clusters NGC 5927 and NGC 6496

Journal Article · Mon Apr 01 04:00:00 EST 1991 · Astronomical Journal; (USA)

DOI:https://doi.org/10.1086/115770· OSTI ID:5759798

Friel, E D; Geisler, D ^[1]

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1. Dominion Astrophysical Observatory, Victoria (Canada) Cerro Tololo Inter-American Observatory, La Serena (Chile)

Washington CCD photometry has been retained for NGC 5927 and NGC 6496, two globular clusters located within several kiloparsecs of the Galactic center. The data reach almost to the main-sequence turnoffs, showing well-defined giant and subgiant branches, and provide accurate photometry for more than 100 giants in each cluster. Photometry of nearby comparison fields makes it possible to estimate the contribution of field stars to the cluster color-magnitude diagrams. Color indices for the giants are used to determine mean cluster metallicities: Fe/H = - 0.25 + or - 0.25 for NGC 5927 and Fe/H = - 1.05 + or - 0.30 for NGC 6496, where the error estimates include both internal and external photometric errors, as well as uncertainties due to reduction technique. Uncertainties in the reddening to NGC 6496 have a significant impact on the ability to determine the metallicity for this cluster from color indices along. A small increase in the reddening E(B - V) from 0.19 to 0.23 would increase the derived abundance to Fe/H = - 0.8, and bring it into better agreement with other abundance indicators. 33 refs.

• OSTI ID: 5759798
• Journal Information: Astronomical Journal; (USA), Journal Name: Astronomical Journal; (USA) Vol. 101; 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
CHARGE-COUPLED DEVICES
CHEMICAL COMPOSITION
ELEMENT ABUNDANCE
ERRORS
GALAXIES
GALAXY NUCLEI
GIANT STARS
MILKY WAY
PHOTOMETRY
SEMICONDUCTOR DEVICES
STAR CLUSTERS
STARS