Studies in Be-Star Variability. 1. A Remarkable Similarity of the Rapid Periodic Light Variations of EM Cep, σ ORI E, and Possibly LQ And
Abstract
The rapid periodic light variations observed in photometric observations of two (possibly three) Be stars (Sigma-Ori E, EM Cep, and LQ And) are analyzed. The variation is characterized by a light curve with two similar but unequal minima and maxima which are reminiscent of the light curves of contact eclipsing binaries. The stars have rather short periods (1.191 days for Sigma-Ori E, 0.086 days for EM Cep, and 0.623 days for LQ And) and are completely lacking in the radial-velocity variations associated with these periods. Spectral variations in Sigma-Ori E correlate well with variations in the photometric period, and this case might also apply to EM Cep and LQ And. It is suspected that the variations are associated with the rotational periods of the stars, thereby confirming the applicability of the magnetic oblique rotator model for He variable stars developed by Shore and Bolton (1982). The light curves of all three stars are reproduced in graphic form.
- Publication:
-
Bulletin of the Astronomical Institutes of Czechoslovakia
- Pub Date:
- August 1984
- Bibcode:
- 1984BAICz..35..193H
- Keywords:
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- B Stars;
- Stellar Luminosity;
- Variable Stars;
- Light Curve;
- Radial Velocity;
- Stellar Models;
- Stellar Rotation;
- Astrophysics