Short-term activity in the gamma2 Velorum system : the O-type supergiant is a nonradially pulsating star.
Abstract
The discovery of photospheric line-profile variability and associated circumstellar effects of the O star in the Gamma(2) Velorum system is reported. The subcomponents drift across the line profiles at different rates. Two pattern speeds hve been tentatively measured to be 125 and 750 km/s/day. The temporal periods are 1.94 and 0.35 day, respectively, while the two spatial periods seem to be identical to one another and are about one-sixth of the stellar circumference. A rotation period in the range of 3-6 days is inferred. Two variable emission-line components straddle the He I 667.8-nm absorption and probably show that the O star has an extended envelope.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- December 1990
- Bibcode:
- 1990A&A...240..105B
- Keywords:
-
- O Stars;
- Stellar Activity;
- Stellar Oscillations;
- Supergiant Stars;
- Absorption Spectra;
- Binary Stars;
- Line Spectra;
- Periodic Variations;
- Stellar Spectra;
- Wolf-Rayet Stars;
- Astrophysics