Oral Presentation

Binary nature revealed in circumstellar spiral-shell patterns

Hyosun Kim (ASIAA), Ronald E. Taam (ASIAA, Northwestern), Sheng-Yuan Liu (ASIAA), I-Ta Hsieh (ASIAA)

It is only very recent that asymptotic giant branch (AGB)
stars reveal the circumstellar spiral patterns with the advent of high resolution and high sensitivity observations. Such patterns can provide possible evidence for the existence of central binary stars embedded in outflowing circumstellar envelopes, which provides an important clue for the late stellar evolution as well as the onset of asymmetrical planetary nebulae. I will review the theoretical model for the binary-induced spiral-shell patterns on the AGB circumstellar envelopes, and the observational aspects in constraining the characteristics of the unknown, conceivable central binary stars.