Atmospheres of Evolved Stars at Optical and Infrared Wavelengths
Abstract
Cool, evolved stars contribute conspicuously to the chemical enrichment of the interstellar medium. They lose dust via their stellar winds, which are triggered by processes in their interior. In particular, the chromospheres of giant K- and M-type stars, and the atmospheres of the most evolved stars on the Asymptotic Giant Branch (AGB), play a crucial role in initiating their mass loss. Recent discoveries have illustrated the power of interferometric optical and infrared observations, which now are capable of resolving structure on giant stars at sub-milliarc second resolution. I will review the previous interferometric results on evolved stars' atmospheres, done with the CHARA array, and the Very Large Telescope Interferometer, and present upcoming observations, showing details on the dynamical structures of atmospheres in giant stars. I will also review recent results obtained with the Hubble Space Telescope (HST) on the chromospheric structure of giant stars. Finally, I will provide insights on the capabilities of the James Webb Space Telescope (JWST), the next large strategic NASA space observatory.
- Publication:
-
American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23531906R