Time: 11:00 h
Author: Tom Millar
In recent years, high spatial resolution observations of the circumstellar envelopes (CSEs) of AGB stars have shown that molecular distributions cannot be characterised by spherically symmetric outflows at constant velocity. The observations show the presence of rings, arcs and clumps in CSEs as well as the presence of complex molecules close to the stellar surface. In this talk, I will discuss some recent work on modelling the chemistry of clumpy outflows in AGB stars and show how this can lead to substantial increases of molecular abundances in the inner CSE. If clumpy structures exist even in the dust formation zone, then it is also possible that UV radiation from stellar sources can influence molecule, and possibly dust, formation.