The Intensity of Certain Lines of he i in the B Stars.
Abstract
The behavior of the He I lines X 4471, 4387, and 4144 is investigated in connection with spectral types determined on the system of the Yerkes spectral atlas for main-sequence stars and for supergiants. In the main-sequence stars the results are similar to those found earlier by Struve, Williams, and Rudnick; in the supergiants, however, the behavior is strikingly different for X 4471, which appears to reach its maximum intensity near O9BO. Attention is called to the peculiar spectrum of the O9 star HD 93521; its spectral peculiarities and large distance from the galactic plane suggest a connection with Baade's Population II.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 1952
- DOI:
- 10.1086/145553
- Bibcode:
- 1952ApJ...115..341A