P59	October 2000

¹ Institut d'Astrophysique et de Géophysique - Université de Liège, Avenue de Cointe 5, 4000 Liège, Belgium

^* Postdoctoral Researcher FNRS, Belgium
^** Research Associate FNRS, Belgium

⁺ Based on observations collected at the European Southern Observatory (La Silla, Chile) and at the Cerro Tololo Inter-American Observatory (CTIO)

Abstract

     We present the very first results of a visible spectroscopy campaign targeting colliding wind candidates of the young open cluster NGC 6231 that are going to be observed with the XMM satellite as part of the Liège Project for Guaranteed Time Observations. We derive new improved orbital solutions ans we discuss the spectral characteristics of these systems. A special attention is paid to the binary star HD 152248. We investigate its HE II 4686 and H lines and their profile variability. We discuss the probable signature of a wind interaction process in order to derive constraints on the properties of the shock region.