Photometry and spectroscopy of the O-type variable HD 167971.
Stahl, O.; Leitherer, C.; Zickgraf, F. -J.; Wolf, B.; Krautter, J.; Mandel, H.; Klare, G.; Forbes, D.; Gilmore, A. C.; Hearnshaw, J.; Strupat, W.; Zirbel, E.
Germany, United States, Canada, New Zealand
Abstract
The authors present photometric and spectroscopic observations of the O-type variable HD 167971. From a period analysis of the visual light-curve they find P = 3.3213 days. Combining the photometric and spectroscopic data they derive a consistent model for the system which can be understood in terms of a close O-type eclipsing binary and a third, more distant companion of spectral type O. The latter star is the most luminous component of the system and dominates the optical and the UV spectrum. The mass loss rate of this star is derived from the Hα- and the UV-line profiles. The authors find M≅ 2×10-6M_sun;yr-1 and v = 3100 km s-1.