1. SMA Observations of the Orion proplyds
Jonathan Williams (IfA)
Sean Andrews (IfA)
David Wilner (CfA)

2. VLA  mass loss rate ~ 10-7 M/yr
HST  radii ~ AU
VLA  mass loss rate ~ 10-7 M/yr
 tevap ~ 105 yr for MMSN (10-2 M)

3. Most solar mass stars form in Orion type environments.
But if tevap ~ 105 yr,
what are the prospects for planet formation?
What is the mass of the inner (< 30 AU) disk that is bound to the star?

4. Need to get to shorter wavelengths!
Mundy et al. 1995
BIMA
Previous millimeter array observations
- isolate individual objects
filter out cloud emission
OVRO
Bally et al. 1998
Need to get to shorter wavelengths!
PdBI
Lada 2000

6. SMA Observations November 2004
Compact array, 341 GHz, 1.5’’ beam
Two tracks  2.7 mJy/beam

7. 0.019 M
0.016 M
0.024 M
0.013 M

8. bremsstrahlung + greybody
(ionized gas + dust)
Submillimeter wavelengths essential to get the dust

9. What about the 18 non-detections?
Average mass
~ 8x10-4 M

10. Odd detection statistics  abrupt mass loss event?
Circular or elliptical orbits?
(Störzer & Hollenbach 2000)

11. An SMA survey of Orion?

12. An SMA survey of Orion? 10 tracks  ~ 20-30 detections?
Disk mass function
Environmental influence
Gas content?

13. David Aguilar