Reference : Wind collisions in three massive stars of Cygnus OB2
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Space science, astronomy & astrophysics
http://hdl.handle.net/2268/160993
Wind collisions in three massive stars of Cygnus OB2
English
Cazorla, Constantin mailto [Université de Liège - ULiège > > GAPHE : Astrophysique observationnelle (sol et espace) >]
Nazé, Yaël mailto [Université de Liège - ULiège > > GAPHE : Astrophysique observationnelle (sol et espace) >]
Rauw, Grégor mailto [Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Sciences spatiales >]
9-Jan-2014
Astronomy and Astrophysics
EDP Sciences
561
A92 (14p)
Yes (verified by ORBi)
International
0004-6361
1432-0746
Les Ulis
France
[en] stars: early-type ; stars: individual: Cyg OB2 #5 ; stars: individual: Cyg OB2 #8A ; stars: individual: Cyg OB2 #12 ; X-rays: stars ; binaries: eclipsing
[en] Aims. We wish to study the origin of the X-ray emission of three massive stars in the CygOB2 association: CygOB2#5, Cyg OB2 #8A, and Cyg OB2 #12. Methods. To this aim, dedicated X-ray observations from XMM-Newton and Swift are used, as well as archival ROSAT and Suzaku data. Results. Our results on Cyg OB2 #8A improve the phase coverage of the orbit and confirm previous studies: the signature of a wind- wind collision is conspicuous. In addition, signatures of a wind-wind collision are also detected in Cyg OB2 #5, but the X-ray emission appears to be associated with the collision between the inner binary and the tertiary component orbiting it with a 6.7 yr period, without a putative collision inside the binary. The X-ray properties strongly constrain the orbital parameters, notably allowing us to discard some proposed orbital solutions. To improve the knowledge of the orbit, we revisit the light curves and radial velocity of the inner binary, looking for reflex motion induced by the third star. Finally, the X-ray emission of Cyg OB2 #12 is also analyzed. It shows a marked decrease in recent years, compatible with either a wind-wind collision in a wide binary or the aftermath of a recent eruption.
Researchers
http://hdl.handle.net/2268/160993
10.1051/0004-6361/201322539

File(s) associated to this reference

Fulltext file(s):

FileCommentaryVersionSizeAccess
Open access
aa22539-13.pdfPublisher postprint887.72 kBView/Open

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.