Molecular Radio Line Observations of AGB-Stars, Post-AGB Objects, and Planetary Nebulae.

摘要

The review summarizes the findings on the kinematics and geometry of circumstellar envelopes around objects at different evolutionary stages obtained through molecular radio line observations. It also examines the validity of two commonly used simple formulae, based on CO and OH emission, for estimating the mass loss rates of these objects. Finally, it is discussed to what extent circumstellar molecular radio line emission can be used to determine the evolutionary status of an object.