[en] 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.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
De Becker, Michaël ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE)
Rauw, Grégor ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE)
Manfroid, Jean ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Language :
English
Title :
A spectroscopic study of the non-thermal radio emitter Cyg OB2#8A: Discovery of a new binary system
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