A Young Stellar Cluster in the Nucleus of NGC 4449

  title={A Young Stellar Cluster in the Nucleus of NGC 4449},
  author={Torsten B{\"o}ker and Roeland P. van der Marel and L. Mazzuca and Hans–Walter Rix and Gregory H. Rudnick and Luis C. Ho and Joseph C. Shields},
  journal={The Astronomical Journal},
  pages={1473 - 1481}
We have obtained 1–2 Å resolution optical echellette spectra of the nuclear star cluster in the nearby starburst galaxy NGC 4449. The light is clearly dominated by a very young (6–10 Myr) population of stars. For our age dating, we have used recent population synthesis models to interpret the observed equivalent width of stellar absorption features such as the H I Balmer series and the Ca II triplet around 8500 Å. We also compare the observed spectrum of the nuclear cluster with synthesized… 


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