1. HI-distribution in the MW
Supervisor: Peter Kalberla
Group #1
Bitten Gullberg
Maria Louise Strandet
Sarolta Zahorecz
Valentina Vacca

2. OUTLINE 1. Scientific aim and method 2. Theoretical background
3. Data presentation
4. Discussion

3. Scientific aim and method
Scientific aim: To explore the HI distribution in the Milky Way and to determine the kinetic spin temperature of filaments
Method: We fit the emission and absorption lines by means of gaussian curves

4. OUTLINE 1. Scientific aim and method 2. Theoretical background
3. Data presentation
4. Discussion

5. Self absorbing HI clouds
Background continuum
Have been subtracted in our data
Foreground HI emission
Can be ignored because we are close (125 pc) to the self absorbing cloud
Background HI emission

6. OUTLINE 1. Scientific aim and method 2. Theoretical background
3. Data presentation
4. Discussion

7. Parkes Telescope Location: Australia, NSW Diameter: 64 m
Telescope and survey
Parkes Telescope
Location: Australia, NSW
Diameter: 64 m
Galactic All Sky Survey

8. Data presentation

9. Data presentation

10. Data presentation

11. Data presentation

12. Data presentation

13. Data presentation

14. Data presentation

15. Data presentation

16. Data presentation

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19. Data presentation

20. OUTLINE 1. Scientific aim and method 2. Theoretical background
3. Data presentation
4. Discussion

21. The kinetic spin temperature
The kinetic spin temperature is calculated as
Where σ is the actual velocity dispersion, where the instrumental broadening has been taken into account
For GASS the instrumental broadening is

22. The kinetic spin temperature
Range: 203 – 325 K
Average: 247 K
Range: 101 – 275 K
Average: 170 K
Very turbulent!

23. The kinetic spin temperature
T = 65 K
T=14 K
Montgomery et al. (1995)

24. Thank you!