Dust formation in the hot massive binary HD 192641=WR 137 (WC7+OB)

Medium band (H' and K') images of the episodic dust-forming, long-period (s imilar to 13 yr) WC7 + OB binary WR 137 were obtained with the Near-Infrare d Camera and Multiobject Spectrometer 2 camera of the Hubble Space Telescop e 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 w ith a total extension of similar to 0." 25. The dust is likely either creat ed or enhanced in the zone of gas shocked by wind-wind collision. We estima te the total mass of the resolved dust features during the 1997-1998 outbur st to be similar to 2 x 10(-7) M. (similar to 0.1M(+)) within a factor of 3 .