The spectrum of HD 125823 (a Centauri).
Abstract
Equivalent widths and profile observations of representative lines in the spectrum of the helium variable HD 125823 (a Centauri) are presented around one cycle of 8.814 days. European Southern Observatory Camera III spectrograms (3.3 A mm1) covering the region A, and Camera II spectrograms covering the region 4800-6600 A at 12.4 A mm -1, are used. The equivalent widths of the hydrogen lines and lines of C ii, 0 ii, Mg II, Si ii, and Ca ii do not vary in a systematic way by a significant amount during the He I cycle, while lines of N II, Si iii, and Fe iii vary in antiphase to the He I lines. The projected rotational velocity is estimated to be 17 km s ' from the cores of the sharp lines, but the wings of these lines are broader than that. Representative profiles are presented of the weak, shallow Fe I lines which appear between phases 0.9 and 0.3 of the He I variation. The origin of these lines is not understood. Subject headings: spectrum variables - stars, individual - variable stars
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1975
- DOI:
- 10.1086/153670
- Bibcode:
- 1975ApJ...199..120U
- Keywords:
-
- Line Spectra;
- Spectral Line Width;
- Spectrum Analysis;
- Stellar Spectra;
- Variable Stars;
- Astronomical Models;
- Helium;
- Stellar Atmospheres;
- Stellar Rotation;
- Tables (Data);
- Astronomy