Scientific Rationale

Mass loss from cool Asymptotic Giant Branch and Red Supergiant stars inputs large amounts of material to the ISM (10-7 to 10-4 Msunyr-1) and leads to the formation of Planetary Nebulae and Supernovae. It is therefore an important process for understanding both galactic ecology and stellar lifecycles. Recent years have seen significant advances in observations and theory of late stages of stellar evolution. Thanks to ALMA, VLTI and other recent telescopes/arrays, spectral lines and dust can now be resolved on scales down to the size of the stars themselves. The new data provide an opportunity to revisit outstanding questions of late stellar evolution: how is mass loss driven in AGB and RSG stars, what is the role of magnetic fields in their evolution, and what is the effect of binarity?

The meeting is planned for when ALMA Cycle 1, and some Cycle 2, results will have been released and VLTI is currently transforming to 2nd generation instruments (MATISSE, GRAVITY) and becoming an imaging machine (e.g. PIONIER). These telescopes provide complementary, high spectral and spatial resolution observations of different layers of the stellar atmosphere and wind species, and this workshop will exploit their synergies for the study of AGB and RSG stars. At the spatial scales probed, temporal variability and kinematical study of the above-mentioned processes are also possible.

In addition, project planning for ALMA, future facilities and instruments such as the E-ELT, mm/submm-VLBI, and a possible extension of VLTI imaging capability and 3rd generation VLTI instruments can take place.