A circumstellar journey-physics and chemistry of AGB stellar winds

Paper i proceeding, 2008

The physics and chemistry of the envelopes of gas and dust that surround stars on the asymptotic giant branch are the subjects of this review. Estimates of stellar mass-loss rates in this phase, as determined through observations and modelling of different circumstellar probes, are discussed. A particular phenomenon of highly episodic mass loss is described. Estimates of circumstellar molecular abundances are compared with expectations from chemical models.