view Abstract Citations (33) References (31) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Spectroscopic evidence for a range in abundances among faint subgiantstars in the globular cluster OME Cen. Bell, R. A. ; Harris, G. L. H. ; Hesser, J. E. ; Cannon, R. D. Abstract Intermediate dispersion spectra are presented for 11 stars on the lower subgiant branch of Omega Cen having B values in the range 16.7-18.4. Five of the stars have radial velocities incompatible with cluster membership, while of the remaining six probable members, five have M/H abundances in the -1.0 to -1.5 range and show signs of carbon depletion. The sixth object, with an M/H value of about -0.5, has an enhanced nitrogen abundance whose factor may be as high as 3.0. The possible reasons for this variation in nitrogen abundance considered are: (1) mixing of the stars during their evolution; (2) differences in abundance at the time of star formation; (3) accretion of material lost by the cluster red giants, and (4) accretion of material lost by a binary comparison. Publication: The Astrophysical Journal Pub Date: October 1981 DOI: 10.1086/159324 Bibcode: 1981ApJ...249..637B Keywords: Abundance; Globular Clusters; Late Stars; Stellar Spectra; Subgiant Stars; Carbon; Nitrogen; Radial Velocity; Red Giant Stars; Spectrum Analysis; Stellar Evolution; Stellar Mass Accretion; Astrophysics full text sources ADS | data products SIMBAD (1)