Nitrogen line spectroscopy of O-stars - II. Surface nitrogen abundances for O-stars in the Large Magellanic Cloud

  title={Nitrogen line spectroscopy of O-stars - II. Surface nitrogen abundances for O-stars in the Large Magellanic Cloud},
  author={J. G. Rivero Gonzalez and Joachim Puls and Francisco Najarro and Ines Brott},
  journal={Astronomy and Astrophysics},
This is the second paper in a series aiming at the analysis of nitrogen abundances in O-type stars, to enable further constraints on the early evolution of massive stars. We investigate the NIV lambda4058 emission line formation, provide nitrogen abundances for a substantial O-star sample in the LMC, and compare our findings with recent predictions from stellar evolutionary models. Stellar and wind parameters are determined by line profile fitting of hydrogen, helium and nitrogen lines, based… 
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