1. The three-dimensional structure of the Large and Small Magellanic Clouds from Red Giant Variables Philip Lah Collaborators: Laszlo Kiss Tim Bedding (University of Sydney)

2. Red Giant Variables Red Giant Variables - 5 distinct period- luminosity relations - Peter Wood discovered in MACHO data 1999 fairly constant infrared magnitudes – vary the most at blue wavelengths period of variation 25-100 days (some have multiple periods)

3. Period-Luminosity Diagram (LMC)

4. The Project See if one can use the period-luminosity relations as a distance indicator Use to measure variation in the structure of the Large & Small Magellanic Clouds Data - OGLE II micro-lensing observations over 4 years (used to derive periods) - 2MASS K magnitudes of stars

5. Large Magellanic Cloud

7. Sky position LMC

8. Period mag LMC

9. LMC Line Fitting

10. LMC Distance Variation

11. Comparison with Subramaniam Data

12. LMC 3D

13. Small Magellanic Cloud

15. Sky position SMC

16. Period mag SMC

17. SMC Line Fitting

18. SMC Distance Variation

19. SMC 3D

20. Conclusions demonstrated that the Red Giant Variables can be use as distance indicators LMC bar inclined and has substructure (warps) SMC found patchy substructure - results less convincing due to larger range in spatial depth of SMC

21. The End

23. Light Curve - MACHO

24. Colour Mag Diagram