A&A 424, L39-L42 (2004)
A Spectroscopic study of the non-thermal radio emitter Cyg OB2 #8A: Discovery of a new binary systemM. De Becker, G. Rauw and J. Manfroid
Institut d'Astrophysique et de Géophysique, Université de Liège, 17, Allée du 6 Août, B5c, 4000 Sart Tilman, Belgium
(Received 7 May 2004 / Accepted 2 August 2004)
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.
Key words: binaries: spectroscopic -- stars: early-type -- stars: fundamental parameters -- stars: individual: Cyg OB2 #8A
© ESO 2004