Probing the clumpy and asymmetric mass loss from evolved stars using molecular emission

Dinh Van Trung, Jeremy Lim, Sabastien Muller & Katat Wong

Institute of Physics, Vietnam Academy of Science and Technology

Evolved stars are usually surrounded by thick and expanding circusmtellar envelopes created by the mass loss process. These circumstellar envelopes are known to be strong sources of molecular emission. Observations of the molecular emission can provide detailed information on the structures and physical conditions within the envelopes, and thus can reveal the mass loss history of the central stars. In this presentation I will focus on the high angular resolution observations of the molecular emission from circumstellar envelopes around asymptotic giant branch (AGB), post-AGB and supergiant stars. The high quality data together with detailed excitation modeling provide clear evidence of the clumpy and asymmetric structure of the circumstellar envelopes. The role of binary shaping of the circumstellar envelopes is also discussed.

Last update: