Extremely α-Enriched Globular Clusters in Early-Type Galaxies:A Step toward the Dawn of Stellar Populations?

@article{Puzia2006ExtremelyG,
  title={Extremely $\alpha$-Enriched Globular Clusters in Early-Type Galaxies:A Step toward the Dawn of Stellar Populations?},
  author={Thomas H. Puzia and Markus Kissler-Patig and Paul Goudfrooij},
  journal={The Astrophysical Journal},
  year={2006},
  volume={648},
  pages={383 - 388}
}
We compare [α/Fe], metallicity, and age distributions of globular clusters in elliptical, lenticular, and spiral galaxies, which we derive from Lick line index measurements. We find a large number of globular clusters in elliptical galaxies that reach significantly higher [α/Fe] values ([α/Fe] > 0.5) than any clusters in lenticular and spiral galaxies. Most of these extremely α-enriched globular clusters are old (t > 8 Gyr), and cover the metallicity range Pub Lcl changemark="ins">-1 ≲ [Z/H… 

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