The Distribution of Circumstellar Dust in Luminous, Heavily Enshrouded Stars.

The spatial distribution of dust in the circumstellar environments of AGB stars, red supergiants, and warm hypergiants varies greatly between objects, but is often not spherical, or even partly so. The geometry of the dust distribution can have a significant influence on the composition and structure of the dust grains, at least at the time we observe them around the star. It may also have a significant impact on the characteristics of the dust that survives to become part of the interstellar medium. Through the use of high resolution imaging and polarimetry, we can begin to probe the geometry of the dust distribution close to the star where it first forms.

This research has been supported in part by NSF grant AST 0205814.