Reference : NGC6231: X-ray Properties of the Early-Type Star Population
Scientific congresses and symposiums : Paper published in a book
Physical, chemical, mathematical & earth Sciences : Space science, astronomy & astrophysics
http://hdl.handle.net/2268/15936
NGC6231: X-ray Properties of the Early-Type Star Population
English
Sana, H. [> > > >]
Nazé, Yaël mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Sciences spatiales >]
Gosset, Eric mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE) >]
Rauw, Grégor mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE) - Sciences spatiales >]
Sung, H. [> > > >]
Vreux, Jean-Marie [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > > ]
2007
Massive Stars in Interactive Binaries
367
109
No
International
[en] Based on a deep XMM-Newton observation of the young open cluster NGC6231, we derive the main X-ray properties of its early-type star population. Among the 610 X-ray sources detected in the field, 42 are associated with early-type stars. We investigate their L[SUB]X[/SUB]/L[SUB]bol[/SUB] relationship and confirm the clear dichotomy between O- and B-type stars. The cut-off line between the two behaviours occurs at L[SUB]bol[/SUB] ~ 10[SUP]38[/SUP] erg s[SUP]-1[/SUP] as previously proposed by Berghöfer et al. (1997). The distinction between single and binary stars is not clear cut, except for the colliding wind system HD152248. The X-ray detected B-stars in NGC6231 appear to be more luminous than predicted from the Berghöfer et al. relation. Though this suggests a bimodal distribution of the B-star X-ray emission, we caution however that these results might be biased by detection limits. Finally we investigate the X-ray variability of the detected sources and we find that about 40% of the X-ray emitters in the field of view present consistent signs of variability in the EPIC instruments. This fraction is much larger than previously thought. About one third of the early-type star population, either singles or binaries, further show variability. These variations do not seem to be exclusively related to binarity and could thus not be systematically interpreted in the framework of a wind-wind collision phenomenon.
Professionals
http://hdl.handle.net/2268/15936
http://adsabs.harvard.edu/abs/2007ASPC..367..109S

File(s) associated to this reference

Fulltext file(s):

FileCommentaryVersionSizeAccess
Restricted access
0411461v1.pdfAuthor postprint219.16 kBRequest copy

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.