Astrophysical: Stellar evolution

  • Talk
    Nitrogen spectroscopy of O-type stars -- On the difficulties to derive reliable abundances
    After a brief outline on the impact of massive stars for the cosmic and galactic evolution, we highlight the role of Nitrogen as a key element to test current...
  • Publication
    NLTE analysis of high-resolution spectra of CSPN
    Preliminary results of new high-resolution and S/N ratio spectra of central stars of planetary nebulae (CSPN) are presented. The atmospheric parameters (Teff...
  • Publication
    NLTE analysis of massive OB stars in open clusters
    The paper presents a new method for deriving stellar masses and distances using the theory of radiatively driven winds as presented by Kudritzki et al. (1989)...
  • Publication
    Observations of massive OB stars
    Preliminary results are presented of spectroscopic analysis of ten young stars in OB associations using high resolution spectra and NLTE calculations. From the...
  • Talk
    On the evolution of rotation and magnetism from solar-like stars to red giants using Kepler data
    More than 40 years ago, Skumanich (1972) showed how rotation and magnetic activity decreased with the age of a solar-like star. While this result was based on...
  • Publication
    On the evolution of supernova remnants. III - Off-centred supernova explosions in pre-existing wind-driven bubbles
    It is shown that supernova explosions inside wind-driven cavities created by progenitors moving across the ambient medium result in a large diversity of remnant...
  • Talk
    On the extreme properties of massive galaxies at high redshifts
    Massive (&#8805 10 11 M⊙) galaxies at high redshift (z &#8805 1.5) remain mysterious objects. Their extremely small sizes (effective radii of 1-2 kpc) make them...
  • Talk
    On the fate of the most massive stars
    Radiation-driven mass loss largely determines the life expectancy of massive stars. I will present our most recent mass-loss predictions for massive stars...
  • Publication
    On the massive star-forming capacity of molecular clouds
    Assuming that photoionization is the self-limiting process for continued star formation, we estimate the maximum number of massive (OB) stars that can form...