Imaging of Stellar Disks and Mass Loss Envelopes in Evolved Stars

P.G. Tuthill, J.D. Monnier, W.C. Danchi
1999 Symposium - International astronomical union  
Interferometric imaging of evolved stars has been performed in the near-IR at the Keck Observatory revealing diffraction-limited structure at unprecedented spatial resolution. By studying the hottest regions of the circumstellar dust shells of a number of bright prototypical objects, we have revealed complex and anisotropic structures in the inner regions where dust nucleation occurs. We find that dramatic dust plumes and clumps dominate the morphology of the circumstellar environment at a
more » ... of a few stellar radii for extreme carbon stars such as IRC+10216 and CIT 6. Furthermore our observations have yielded near-IR diameters and images of the stellar photospheres of nearby red giant and supergiant stars. With the additional benefit of multi-epoch observations, we have begun to investigate the time-evolution of our enshrouded objects as dust is created and accelerated away from the nucleation zone. Armed with such a powerful new set of observational constraints, we are able to address contemporary problems such as the origin of structure in PNe, the physics of mass loss, and the dynamical properties of Mira pulsation.
doi:10.1017/s0074180900203240 fatcat:zubl7xfkvjedlnfgg3mnhrfxju