Stellar wind collision and dust formation in long-period, heavily interacting Wolf-Rayet binaries

Abstract

I estimate the rate of mass loss in the form of cold dense gas from a wide Wolf-Rayet binary like WR 140. At some distance from the binary, this gas can form a dust shell and reradiate the UV radiation in the IR region. In the case of WR 140 which has a high eccentricity the observed IR outbursts may be caused by the strong increase of the cold dense gas outflow from WR 140 at the periastron.