Carbon isotope ratios in giant stars of the old galactic cluster NGC 7789

Abstract

view Abstract Citations (15) References (45) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Carbon Isotope Ratios in Giant Stars of the Old Galactic Cluster NGC 7789 Sneden, C. ; Pilachowski, C. A. Abstract Carbon isotope ratios have been derived for seven giant stars in the old open cluster NGC 7789. High-resolution, high signal-to-noise spectra of the CN red system bands in these stars were obtained with the KPNO 4 m Cassegrain echelle spectrograph and a CCD camera. (C-13)N features were detected easily in all cluster stars, and isotope ratios in the range C-12/C-13 = 10-30 were derived. The isotope ratios of most stars are normal for K giants possessing convective envelopes and show no correlations with effective temperatures and with lithium abundances. However, one cluster star has both very high lithium and the lowest carbon isotope ratio. It is speculated that this star either is an asymptotic giant branch star or a weak G-band star. Publication: The Astrophysical Journal Pub Date: February 1986 DOI: 10.1086/163949 Bibcode: 1986ApJ...301..860S Keywords: Carbon Isotopes; Giant Stars; Star Clusters; Stellar Composition; Abundance; Asymptotic Giant Branch Stars; Carbon 12; Carbon 13; Cn Emission; K Stars; Lithium; Open Clusters; Stellar Envelopes; Stellar Spectra; Stellar Temperature; Astrophysics; CLUSTERS: OPEN; STARS: ABUNDANCES; STARS: LATE-TYPE full text sources ADS | data products SIMBAD (1)