Massive Binary WR 112 and Properties of Wolf-Rayet Dust

摘要

Some hot, massive, Population I Wolf-Rayet (W-R) stars of the carbon subclass are known to be prolific dust producers. How dust can form in such a hostile environment remains a mystery. Here we report the discovery of a relatively cool, extended, multiarc dust envelope around the star WR 112, most likely formed by wind-wind collision in a long-period binary system. We derive the binary orbital parameters, the dust temperature, and the dust mass distributions in the envelope. We find that amorphous carbon is a main constituent of the dust, in agreement with earlier estimates and theoretical predictions.