A Spectroscopic study of the non-thermal radio emitter Cyg OB2 #8A: Discovery of a new binary system
Abstract
We present the results of a spectroscopic campaign revealing that the non-thermal radio emitter Cyg OB2 #8A is an O6 + O5.5 binary system. We propose the very first orbital solution indicating a period of about 21.9 days. The system appears to be eccentric (0.24 ± 0.04) and is likely seen under a rather low inclination angle. The mass ratio of the components is close to unity. The impact of the binarity of this star in the framework of our understanding of non-thermal radio emission from early-type stars is briefly discussed.
Based on observations collected at the Observatoire de Haute Provence, France.- Publication:
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Astronomy and Astrophysics
- Pub Date:
- September 2004
- DOI:
- 10.1051/0004-6361:200400049
- arXiv:
- arXiv:astro-ph/0408027
- Bibcode:
- 2004A&A...424L..39D
- Keywords:
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- binaries: spectroscopic;
- stars: early-type;
- stars: fundamental parameters;
- stars: individual: Cyg OB2 #8A;
- Astrophysics
- E-Print:
- 4 pages, 3 postscript figures, accepted by A&