1. Mass Loss from Galactic Bulge AGB stars
Margaret Meixner (STScI/ visiting Scientist at Harvard-Smithsonian CfA)
Nimesh Patel, Dave Riebel, Ben Sargent, Sundar Srinivasan, Ken Young

2. Why Galactic Bulge? Known Distance: 8 kpc (Reid 1993)
Extreme environment
High metallicity: peak at -0.3, but wide range: -1<[Fe/H]<1
ISOGal studies reveal a population of AGB star candidates suitable for followup (Omont et al.)
Prior studies show that all AGB stars in bulge are oxygen rich, with silicate dust features (Blommaert et al.)

3. ISOGal sample: spectroscopy of 107 candidate AGB stars
Schulteis et al. 2003

4. Metallicity of Bulge ISOGal sample
Solar
neigh.
Schulteis et al. 2003

5. Mass Loss rate from IR
Schulteis et al. 2003

6. SMA project:
Use SMA to spatially filter the foreground CO cloud emission, and detect the point source AGB molecular winds of Galactic Bulge AGB stars.
Use extended SMA configuration, and observe two AGB stars per track.
Goal: to measure gas mass-loss rates, compare to dust mass-loss rates and estimate dust to gas mass ratios
Data taken last week…

7. Vexp V0 Vexp Vexp Vexp Jy V0+Vexp V0-Vexp V0 V0-Vexp V0 V0+Vexp
The other attractive aspect of evolved stars are their simplicity. The channel maps of evolved stars reveal their 3 dimensional structure. Each slice acts as successive cross-cuts through the circumstellar envelope of the star. I’ll spend the rest of my talk on more recent results pursued by myself with my students.
I will be showing a number of channel maps for this data
Set and this slide
V0+Vexp
V0+Vexp
V0-Vexp V0

8. Mass Loss rates from CO Beam size CO abundance Distance
Velocity integrated intensity
Knapp & Morris (1985)
Ramstedt et al. (2008)

9. Prior work: CO detected in Galactic AGB stars/ OH-IR stars:
Winnberg et al. 2009

10. CO detected in Galactic AGB stars/ OH-IR stars: OH0.3-0.2
Winnberg et al. 2009

11. CO detected in Galactic AGB stars/ OH-IR stars: OH 359.762
Winnberg et al. 2009

12. Our SMA sample

13. Galactic Bulge: A12, OH

14. Galactic Bulge: A12, OH

15. Galactic Bulge: A51, OH

16. Galactic Bulge: A51, OH

17. Preliminary results from SMA sample

18. Future Prospects
Continue this galactic bulge project to collect larger numbers and statistics
This project demonstrates an approach that could be used for LMC and SMC AGB samples, but with ALMA