Suzaku observations of the massive twin star HD159176
Abstract
HD159176 is a close binary system which is composed with O7V+O7V type stars. The system is in the young open cluster NGC6383 with a distance of about 1.5 kpc. With almost the same masses, the two stars orbit circularly with a separation of two stellar radii with an orbital period of 3.367 days (Pachoulakis 1995, MNRAS, 280, 153). On this target, one report exists which treated the results of an XMM-Newton observation which was executed in 2004. To investigate the long-term variability, we observed the binary on Feb. 19th 2010 with Suzaku satellite. The Suzaku data showed spectral hardening above 2 keV and showed brighter flux by twice than that of XMM-Newton. We will discuss the origin of the spectral changes in the poster.
- Publication:
-
The First Year of MAXI: Monitoring Variable X-ray Sources
- Pub Date:
- December 2010
- Bibcode:
- 2010fym..confP..36Y