Dust Formation in Hot Stellar Winds

Abstract

WC-type Wolf-Rayet stars show episodic or persistent infrared emission attributed to amorphous carbon grains forming in their winds. The process of dust formation in the hydrogen-poor environments characteristic of WC winds is reviewed and compared to the chemical pathway to soot particle production in AGB stars. Emphasis is put on the formation of the dust precursors, and the physical conditions necessary to nucleate them in WC winds. In particular, it is concluded that dust formation around WC stars occurs in a dense, largely neutral, circumstellar disk.