... HD 159176

Based on observations with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA).

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...1,

Research Associate FNRS (Belgium).

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...

We explored higher velocity values to try to fit this high energy tail with the colliding wind model. However, these models yield an increase of the intensity of the Fe K line at about 6.7 keV up to a level that is totally inconsistent with our data.

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... kpc

With m_V=5.64 (FitzGerald et al. 1978) corrected for the reddening ( A_V=1.12) and M_V=-4.8 (Conti & Alschuler 1971) for a typical O7V star, leading to M_V=-5.55 for an O7V + O7V system, we infer a distance of about 1.0 kpc only. With M_V=-5.2 (Schmidt-Kaler 1982), the calculated distance is about 1.2 kpc.

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