2.  !

4. WAVELENGTH SHIFTS IN SOLAR-TYPE SPECTRA  ! Dainis Dravins, Lennart Lindegren, Hans-Günter Ludwig, Søren Madsen Lund Observatory, Sweden Cool Stars 13, Hamburg, July 2004

5. WAVELENGTH SHIFTS !  Usually interpreted as “Radial velocity”

6. "Definition" of radial velocity "The radial component is stellar movement toward or away from us. This motion must be measured from a star's spectrum." C.De Pree & A.Axelrod: The Complete Idiot's Guide to Astronomy, p.258 (1999)

7. Astrometric radial velocities I Dravins, Lindegren & Madsen, A&A 348, 1040

8. Astrometric radial velocities II Dravins, Lindegren & Madsen, A&A 348, 1040

9. Astrometric radial velocities III Dravins, Lindegren & Madsen, A&A 348, 1040

10. Pleiades from Hipparcos Proper motions over 120,000 years

11. STARPATHS (200,000 y) Madsen, Dravins & Lindegren, A&A 381, 446

12. Hyades from Hipparcos D. Dravins, IAU Symp. 215 (2004)

13. Hyades lineshifts Madsen, Dravins & Lindegren, A&A 381, 446

14. Gravitational redshifts D. Dravins IAU Symp. 210

15. STELLAR GRANULATION Hans-Günter Ludwig (Lund)

16. “Beta Hydri” [G2 IV] Synthetic Fe I line & mirror profile Dravins, Lindegren, Nordlund & VandenBerg, ApJ 403, 385

17. Lineshift & stellar rotation Madsen, Dravins & Lindegren, A&A 381, 446 & Dravins, IAU Symp. 215

18. Atmospheric shockwaves (Hartmut Holweger, Kiel)

19. PROGRESS IN SCIENCE is driven by...  Confrontation between theory and observation  Falsification of theoretical hypotheses  New observational measures requiring explanation

20. PROGRESS IN SCIENCE is not driven by...  Agreement between theory and observation (when they agree, not much new can be learned)

21. PROGRESS IN STELLAR PHYSICS Requires disagreement between theory and observation !

22. Non-LTE in convective lineshifts Dravins & Nordlund, A&A 228, 184 Dravins, IAU Symp. 210

23. Fe II lineshifts at solar disk center Dravins, IAU Symp. 210 Solar data: Allende Prieto & García López, A&AS 131, 341 Laboratory wavelengths: S. Johansson (Lund)

24. Fe II lineshifts at solar disk center Aleksey Gadun 2-D models by Aleksey Gadun, Kyiv, Ukraine Dravins, IAU Symp. 210

25. Ni I lineshifts at solar disk center Dravins, IAU Symp. 210 Solar data: Allende Prieto & García López, A&AS 131, 341 Laboratory wavelengths: U. Litzén, J.W.Brault, A.P.Thorne, Phys.Scr. 47, 628

26. 429 Ti I bisectors at solar disk center Solar data: “Hamburg photosphere” H. Neckel, Solar Phys. 184, 421 Kurucz et al.: Solar Flux Atlas from 296 to 1300 nm Laboratory wavelengths: P. Forsberg, Phys.Scr. 44, 446 U. Litzén (Lund)

27. Same spectral line in different stars Dravins, IAU Symp. 210 Adapted from Dravins & Nordlund, A&A 228, 203

28. IMAGING STELLAR SURFACES ESO VLTI : AT1 and domes of the 8.2 m unit telescopes

29. Same spectral line in different stars Adapted from Dravins & Nordlund, A&A 228, 203

30. IMAGING STELLAR SURFACES

31. Optical VLA Antoine Labeyrie (Laboratoire d'Interférométrie Stellaire et Exo-planétaire)

32. WAVELENGTH SHIFTS ! A new diagnostic tool for stellar physics enabled by...  Astrometric radial velocities throughout the Hertzsprung-Russell diagram  High-resolution spectrometers with accurate wavelength calibration  Accurate laboratory wavelengths for several atomic species

33. The End

34. ...

35. Astrometric radial velocities from perspective acceleration Dravins, Lindegren & Madsen, A&A 348, 1040

36. UNDERSTANDING STELLAR SURFACES theory and observations interact about...  Spectral-line strengths  Spectral-line widths  Line-profile shapes  Line asymmetries and bisector patterns  Time variability in irradiance and spectrum  Stellar surface imaging  Relative & absolute wavelength shifts