Formation of Dust in Hostile Environments — What We Learn from Observing Wolf-Rayet Stars

摘要: The formation of dust in Wolf-Rayet stellar winds presents challenges to our understanding on account the stars’ strong UV radiation fields. These would heat grains sublimation unless they were shielded or restricted significant distances (~ 100 AU) from stars where wind densities appear be too low allow formation. Valuable clues are provided by observations episodic different mass- and time-scales, especially major outbursts modulated orbital motion binaries. Wind inhomogeneities all scales — global wind-compressed zones arising rotation, high-density wakes produced colliding-wind binaries smaller clumps significant. observational evidence for these effects is reviewed.