The Ionizing Stars of Extragalactic H II Regions

@article{Bresolin1999TheIS,
  title={The Ionizing Stars of Extragalactic H II Regions},
  author={Fabio Bresolin and Robert C. Kennicutt and Donald Roy Garnett},
  journal={The Astrophysical Journal},
  year={1999},
  volume={510},
  pages={104-124}
}
Medium-resolution spectra from 3650 to 10000 A are presented for 96 giant H II regions distributed in 20 spiral galaxies. In order to interpret the data, we have calculated two separate grids of photoionization models, adopting single-star atmospheres (Kurucz) and star clusters synthesized with different initial mass functions (IMFs) as ionizing sources. Additional models were computed with more recent non-LTE stellar atmospheres, in order to check the effects of different stellar ionizing… 
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