2002A&A...384.1012P

We discuss the variability of WR86 (WC7 (+B0 III)), a known visual binary, confirmed by Hubble Space Telescope observations (Niemela et al., 1998AJ....115.2047N). Photometric observations show a fairly smooth light curve with a time scale of ∼3.5h and a light amplitude of ∼0.01mag . Because of the spectral classification of the visual companion (B0 III) it might well be a β-Cephei star. From observations taken in 1989, 1990 and 1995 we derive two photometric frequencies, 6.914c/d and 7.236c/d, where only the latter is given in the recent VIIth catalogue of galactic Wolf-Rayet stars (van der Hucht, 2001NewAR..45..135V). Our spectroscopy reveals a slightly variable WR star and almost certainly a pulsating companion. Comparison with stellar models suggests that WR86 consists of a 20M_☉ β-Cephei star in combination with a WR star of initial mass 40M_☉, at Z=0.04. We derive a distance to WR86 of 2.1±0.8kpc.