Dust Formation in the Hot Massive Binary HD 192641 = WR 137 (WC7 + OB)

Abstract

Medium band (H' and K') images of the episodic dust-forming, long-period (~13 yr) WC7 + OB binary WR 137 were obtained with the Near-Infrared Camera and Multiobject Spectrometer 2 camera of the Hubble Space Telescope during periastron passage in 1997-1998. We have resolved IR-emitting dust in the close environment of this system. The dust emission occurs in a few clumps within about 0.5" of the star, as well as in a jetlike structure with a total extension of ~0.25". The dust is likely either created or enhanced in the zone of gas shocked by wind-wind collision. We estimate the total mass of the resolved dust features during the 1997-1998 outburst to be ~2×10^-7 M_solar (~0.1M_⊕) within a factor of 3.

Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.