Stars with Strong Cyanogen Absorption
Abstract
This investigation attempts to define the properties of G8-K4 giants with abnormally strong CN ( Iiss Roman's "4150 stars"). Slit spectwgrams were obtained of stars that had been suspected to have strong CN on objective-prism plates or that were noted in the literature as having strong CN. A list of 146 stars with strong CN is given. Five groups (all G8-K2 stars, G8-K2 III-IV stars, G8-K2 stars with moderately strong CN, G8-K2 stars with quite strong CN, and K3-K4 stars) have been formed from these stars, and for each group a statistical parallax and a mean visual absolute magnitude were calculated. Visual absolute magnitudes of +1.3 + 0.4, +1.5 l 0.6, +1.4+0.5, +1.3 + 0.5, and +1.0+0.7 (m.e.), respectively were found for the above groups. The low absolute magnitude of the strong-CN giants places them, in the H-R diagram, near the loci for old open clusters. Spectroscopically they appear similar to the red giants in the old open clusters. Evidence indicates that they have masses near I . Elemental abundances are discussed, but no conclusion is reached.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1971
- DOI:
- 10.1086/150747
- Bibcode:
- 1971ApJ...163...75S