Model Dust Envelopes Around Silicate Carbon Stars

Abstract

We have modeled dust envelopes around silicate carbon stars using optical properties for a mixture of amorphous carbon and silicate dust grains paying close attention to the infrared observations of the stars. The 4 stars show various properties in chemistry and location of the dust shell. We expect that the objects that fit a simple detached silicate dust shell model could be in the transition phase of the stellar chemistry. For binary system objects, we find that a mixed dust chemistry model would be necessary.

Keywords

• circumstellar matter
• stars: AGB and post-AGB
• infrared: stars
• dust: extinction
• radiative transfer