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WAVELENGTH SHIFTS IN SOLAR-TYPE SPECTRA ! Dainis Dravins, Lennart Lindegren, Hans-Günter Ludwig, Søren Madsen Lund Observatory, Sweden Cool Stars 13, Hamburg, July 2004
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WAVELENGTH SHIFTS ! Usually interpreted as “Radial velocity”
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"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)
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Astrometric radial velocities I Dravins, Lindegren & Madsen, A&A 348, 1040
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Astrometric radial velocities II Dravins, Lindegren & Madsen, A&A 348, 1040
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Astrometric radial velocities III Dravins, Lindegren & Madsen, A&A 348, 1040
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Pleiades from Hipparcos Proper motions over 120,000 years
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STARPATHS (200,000 y) Madsen, Dravins & Lindegren, A&A 381, 446
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Hyades from Hipparcos D. Dravins, IAU Symp. 215 (2004)
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Hyades lineshifts Madsen, Dravins & Lindegren, A&A 381, 446
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Gravitational redshifts D. Dravins IAU Symp. 210
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STELLAR GRANULATION Hans-Günter Ludwig (Lund)
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“Beta Hydri” [G2 IV] Synthetic Fe I line & mirror profile Dravins, Lindegren, Nordlund & VandenBerg, ApJ 403, 385
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Lineshift & stellar rotation Madsen, Dravins & Lindegren, A&A 381, 446 & Dravins, IAU Symp. 215
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Atmospheric shockwaves (Hartmut Holweger, Kiel)
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PROGRESS IN SCIENCE is driven by... Confrontation between theory and observation Falsification of theoretical hypotheses New observational measures requiring explanation
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PROGRESS IN SCIENCE is not driven by... Agreement between theory and observation (when they agree, not much new can be learned)
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PROGRESS IN STELLAR PHYSICS Requires disagreement between theory and observation !
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Non-LTE in convective lineshifts Dravins & Nordlund, A&A 228, 184 Dravins, IAU Symp. 210
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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)
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Fe II lineshifts at solar disk center Aleksey Gadun 2-D models by Aleksey Gadun, Kyiv, Ukraine Dravins, IAU Symp. 210
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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
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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)
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Same spectral line in different stars Dravins, IAU Symp. 210 Adapted from Dravins & Nordlund, A&A 228, 203
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IMAGING STELLAR SURFACES ESO VLTI : AT1 and domes of the 8.2 m unit telescopes
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Same spectral line in different stars Adapted from Dravins & Nordlund, A&A 228, 203
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IMAGING STELLAR SURFACES
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Optical VLA Antoine Labeyrie (Laboratoire d'Interférométrie Stellaire et Exo-planétaire)
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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
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The End
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