Washington photometry of the very metal poor globular cluster M68

Journal Article · Thu Jun 01 04:00:00 EDT 1989 · Astrophysical Journal; (USA)

DOI:https://doi.org/10.1086/167483· OSTI ID:5470203

Minniti, D; Claria, J J ^[1]

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1. Observatorio Astronomico, Cordoba (Argentina)

Photometry on the Washington system is presented for a sample of 11 red giants of the very metal poor globular cluster M68 (= NGC 4590). Abundances are determined for six stars that fall within the range of the revised CMT1T2 calibrations. No firm evidence for any intrinsic differences in CN strengths among the cluster giants is detected. The average metallicity for M68 is found to be M/H abundance ratio = -2.63 + or - 0.14, from the Fe+CNO-sensitive Delta(C-M) blue-green index. This extremely low value places M68 as more metal-poor than any other globular cluster known in the Galaxy. 45 refs.

• OSTI ID: 5470203
• Journal Information: Astrophysical Journal; (USA), Journal Name: Astrophysical Journal; (USA) Vol. 341; ISSN ASJOA; ISSN 0004-637X
• 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
ALKALINE EARTH METALS
CALIBRATION
CHEMICAL COMPOSITION
ELEMENTS
GALAXIES
GIANT STARS
HYDROGEN
MAGNESIUM
METALS
MILKY WAY
NONMETALS
PHOTOMETRY
STAR CLUSTERS
STARS
TEMPERATURE MEASUREMENT