The XMM-Newton view of Plaskett's star and its surroundings
Linder, N.[Institut d'Astrophysique et de Géophysique, Université de Liège, Belgium) AB(Institut d'Astrophysique et de Géophysique, Université de Liège, Belgium]
Rauw, Grégor[Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE) - Sciences spatiales >]
Massive Stars and High-Energy Emission in OB Associations
[en] XMM data of Plaskett's star (HD 47129) are used in order to analyse its X-ray spectrum and variability and hence to derive further constraints on the wind interaction in this early-type binary (O6 I + O7.5 I) system. Combining the information provided by the EPIC and RGS instruments, we find that the X-ray spectrum of Plaskett's star is dominated by thermal plasma at lower energies, whereas the higher energy part (> 3 keV) could probably best be represented by a featureless power law component since we do not detect a significant Fe-K line. Our tests also suggest that an overabundance in nitrogen by a factor Ë 6 might be indicated to best represent the RGS spectrum. On the other hand, 71 X-ray sources have been detected in Plaskett's star field of view and most of them have counterparts in near-IR colours that are consistent with slightly reddened main-sequence objects. Actually, a sizeable fraction of the X-ray sources in the EPIC images could be either foreground or background sources with no direct connection to HD 47129.