Galactic AGB stars from the IPHAS survey

Abstract

The INT Photometric H-Alpha Survey (IPHAS) is particular effective in tracing asymptotic giant branch (AGB) stars across the Galactic disk due to its use of broad-band r' and i' filters, and the clear separation of the dwarf and giant branches in the colour-colour diagram. Here we discuss some results from our studies of the Galactic AGB population that has been revealed by IPHAS. This includes a photometric study, our spectroscopic follow-up campaign, and the photometric technique that allows us to separate O-rich, S-type and carbon stars across the entire Galactic disk based on their IPHAS photometry alone. We also discuss the potential impact of this technique on our understanding of the dredge-up process in AGB stars, Galactic chemical evolution, and the structure and properties of the Galactic disk.Comment: Talk at the The Galactic Plane, in depth and across the spectrum, Special Session 8 at the IAU General Assembly 2009, Highlights of Astronomy Volume 15, Janet Drew and Melvin Hoare, ed