1. AJ Mesko Ian Wagner Stefanie Milam Susanna Widicus Weaver
PROBING GAS PHASE CHEMISTRY ABOVE ICE SURFACES WITH MILLIMETER/ SUBMILLIMETER SPECTROSCOPY
The Trifid Nebula, NASA
AJ Mesko
Ian Wagner
Stefanie Milam
Susanna Widicus Weaver
The Trifid Nebula

2. Why is Ice Important Icy Grain Chemistry Our Experiment
The Spectrometer
Proof of Concept
Future Experimentation

3. Icy Grain Chemistry

5. What we do
Analyzing the gas phase products of Icy Grain Reactions by mm/sub-mm Spectroscopy
UV Lamp
Photolyzing Radiation
CH3OH
mm/sub-mm source
.OH
H2O
Detector
.CH3O
H2O
CH3OH
CH3OH
H2O
CH3OH
H2O
Gold Substrate
Heating

7. Why We Do It
Gain information on chemical mechanisms by which COMs can form by icy grain chemistry.
Analyze the effects that different ice compositions and physical properties have on the formation of COMs

8. The Budget Spectrometer
Built mostly of borrowed parts and on a strict budget
Cryopad Setup 1
Liquid Helium Cryostat
Sapphire windows
Gold substrate on cold head
Say it was the Leiden group who developed instead of butchering the name
1. van Broekhuizen, F. 2005, Ph.D. Thesis, Leiden University

9. Temperature Controller Microwave Synthisizer
Multiplier Chain
Cryostat
To pump UV
Lamp
Sample
Line
Detector
Lock In Amplifier
Temperature Controller
Microwave Synthisizer
CPU

10. Temperature Programmed Desorption of Pure Water Ices
Proof of Concept
Temperature Programmed Desorption of Pure Water Ices

12. Comperable as to what was seen by Fraiser et al 2001

13. Proof of Concept Continued:
Temperature Programmed Desorption of Pure Methanol Ice

16. Conclusions
A working mm/sub-mm spectrometer capable of detecting desorption products has been built
Results from other Temperature programmed desorption experiments of pure water2 are in agreement with those produced by this instrument
2. Fraser et. Al 2001

17. The Future Photolysis and photodesorption testing
The Addition of RAIRS for solid phase analysis
A Dirty Chamber
Water/organic mixture studies
Effect of Ice thickness and crystallinity
Gas phase photolysis and thermal product studies
Reflection Absorption InfraRed Spec

18. Acknowledgements
Danna Qasim The Widicus Weaver Research Group Emory University NASA GSFC SIF Program