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Stellar Atmospheres: Literature

Stellar Atmospheres: Literature. Dimitri Mihalas Stellar Atmospheres, W.H. Freeman, San Francisco Albrecht Unsöld Physik der Sternatmosphären, Springer Verlag (in German) Rob Rutten Lecture Notes Radiative Transfer in Stellar Atmospheres http://www.fys.ruu.nl/~rutten/node20.html. Physics

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Stellar Atmospheres: Literature

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  1. Stellar Atmospheres: Literature Dimitri Mihalas Stellar Atmospheres, W.H. Freeman, San Francisco Albrecht Unsöld Physik der Sternatmosphären, Springer Verlag (in German) Rob Rutten Lecture Notes Radiative Transfer in Stellar Atmospheres http://www.fys.ruu.nl/~rutten/node20.html

  2. Physics Stellar atmospheres as laboratories Plasma-, atomic-, and molecular physics, hydrodynamics, thermodynamics Basic research Technical application Astronomy Spectral analysis of stars Structure and evolution of stars Galaxy evolution Evolution of the Universe Why physics of stellar atmospheres?

  3. Magnetic fields in white dwarfs and neutron stars • Shift of spectral lines with increasing field strength

  4. 100 R  4 1026 W 1 R  =700000Km L~R2 T4eff 0.01 R  5800K Hertzsprung Russell Diagram

  5. Massive stars

  6. Chemical evolution of the Galaxy Carretta et al. 2002, AJ 124, 481

  7. SN movie

  8. SN Ia

  9. SN Ia cosmology • M,  • 0 , 1 • 0.5, 0.5 • 1 , 0 • 1.5, -.5 • 0 , 0 • , 0 • , 0 Redshift z

  10. SN Ia Kosmologie 

  11. Uranium-Thorium clock

  12. Stellar atmosphere – definition • From outside visible, observable layers of the star • Layers from which radiation can escape into space • Dimension • Not stellar interior (optically thick) • No nebula, ISM, IGM, etc. (optically thin) • But: chromospheres, coronae, stellar winds, accretion disks and planetary atmospheres are closely related topics

  13. Sonne

  14. Fraunhofer lines

  15. Intensity Wavelength / nm Spectrum - schematically

  16. Spectrum formation

  17. Formation of absorption lines outer boundary Interior observer continuum line center continuum stellar atmosphere intensity

  18. Line formation / stellar spectral types temperature structure spectral line temperature flux depth / km wavelength interior

  19. A7 F3 O5 O7 F8 B4 G2 B6 A1 G5 A5 A8 G8 A9 The spectral types on the main sequence • O B A F G K M

  20. A7 F3 F8 G2 G5 G8 Die Spektraltypen der Hauptreihe • O B A F G K M F6 F8 G1 G6 G9 K4 K5

  21. M9 L3 L5 L8 Classification scheme

  22. Classification scheme T dwarfs

  23. Stellar atmosphere – definition • From outside visible, observable layers of the star • Layers from which radiation can escape into space • Dimension • Not stellar interior (optically thick) • No nebula, ISM, IGM, etc. (optically thin) • But: chromospheres, coronae, stellar winds, accretion disks and planetary atmospheres are closely related topics

  24. Calar Alto (Spain) 3.5m telescope Optical telescopes

  25. ESO/VLT Optical telescopes

  26. flux wavelength / Å UV / EUV observations Why is it important? flux wavelength / Å

  27. UV/optical telescopes HST

  28. X-ray telescopes XMM

  29. Gamma-ray telescopes INTEGRAL

  30. Infrared observatories JWST ISO

  31. Sub-mm telescopes

  32. Stellar atmosphere – definition • From outside visible, observable layers of the star • Layers from which radiation can escape into space • Dimension • Not stellar interior (optically thick) • No nebula, ISM, IGM, etc. (optically thin) • But: chromospheres, coronae, stellar winds, accretion disks and planetary atmospheres are closely related topics

  33. PN – NGC6751 - HST

  34. Planetary nebula spectrum

  35. ISM spectrum

  36. Quasar + IGM spectrum

  37. Stellar atmosphere – definition • From outside visible, observable layers of the star • Layers from which radiation can escape into space • Dimension • Not stellar interior (optically thick) • No nebula, ISM, IGM, etc. (optically thin) • But: chromospheres, coronae, stellar winds, accretion disks and planetary atmospheres are closely related topics

  38. Eta Carinae - HST

  39. Stellar wind spectrum

  40. Formation of wind spectrum (P Cygni line profiles)

  41. Stellar winds – P Cyg profiles

  42. Accretion disks

  43. AM CVn disk spectrum models

  44. Temperature structure of an accretion disk Height [km] Distance from star [km]

  45. Planetary atmospheres

  46. Shape of line profile: Temperature Film Density Film Abundance Film Rotation Turbulence Magnetic field Line position: Chemical composition Velocities Redshift Temporal variation: Companion Surface structure Spots Pulsation Quantitative spectral analyses – what can we learn?

  47. Zeeman effect

  48. Magnetic fields L l optical spectrum spectrum of a white dwarf (PG 1658+440) with field strength of about 5 MG circular polarization position of line components

  49. Magnetic fields L optical spectrum White dwarf Grw+70 8247 B=300MG Circular polarization position of line components

  50. Velocity fields ~ 0.01Å Solar disk distance / 1000km time / min Distance / 1000 km Wavelength / Å

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