High-resolution spectra of stars in globular clusters. VI - Oxygen-deficient red giant stars in M13

Journal Article · Wed May 01 00:00:00 EDT 1991 · Astronomical Journal; (United States)

DOI:https://doi.org/10.1086/115798· OSTI ID:5550789

Brown, J A; Wallerstein, G; Oke, J B ^[1]

---

1. Washington, University, Seattle Palomar Observatory, Pasadena, CA (USA)

From high-resolution, high signal-to-noise spectra, abundances of carbon, nitrogen, and oxygen and the C-12/C-13 ratio for five red giants in M13, including star II-67, which has previously been reported to be deficient in oxygen have been determined. Three of the five stars exhibit substantial oxygen deficiencies; O/Fe values range from +0.5 to less than about 0.3. The sum of the CNO nuclides is the same for all stars, which is interpreted as evidence that mixing of CNO-cycled material into the envelope is the cause of the variations in oxygen abundance. 41 refs.

• OSTI ID: 5550789
• Journal Information: Astronomical Journal; (United States), Vol. 101; ISSN 0004-6256
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
RED GIANT STARS
CHEMICAL COMPOSITION
CARBON
CARBON ISOTOPES
CNO CYCLE
ELEMENT ABUNDANCE
IRON
MIXING
NITROGEN
OXYGEN
STAR CLUSTERS
VARIATIONS
ABUNDANCE
ELEMENTS
GIANT STARS
ISOTOPES
METALS
NONMETALS
STAR BURNING
STARS
TRANSITION ELEMENTS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources