Quantitative spectroscopy of ba-type supergiants

  title={Quantitative spectroscopy of ba-type supergiants},
  author={Norbert Przybilla and Keith Butler and Sylvia R. Becker and Rolf Peter Kudritzki},
  journal={Astronomy and Astrophysics},
Luminous BA-type supergiants have enormous potential for modern astrophysics. They allow topics ranging from non-LTE physics and the evolution of massive stars to the chemical evolution of galaxies and cosmology to be addressed. A hybrid non-LTE technique for the quantitative spectroscopy of these stars is discussed. Thorough tests and first applications of the spectrum synthesis method are presented for the bright Galactic objects η Leo (A0 Ib), HD 111613 (A2 Iabe), HD 92207 (A0 Iae) and β Ori… 
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