Globular Clusters with the Extended Horizontal-Branch as Remaining Cores of Galaxy Building Blocks

  • Young-Wook Lee
  • Hansung B. Gim
  • Chul Chung
Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP)


The relics of building blocks that made stellar halo and bulge are yet to be discovered unless they were completely disrupted throughout the history of the Galaxy. Here we suggest that about 25% of the Milky Way globular clusters have characteristics of the remaining cores of these early building blocks rather than genuine star clusters. They are clearly distinct from other normal globular clusters in the presence of extended horizontal-branch and multiple stellar populations, in mass (brightness), and most importantly in orbital kinematics. Based on this result, a three-stage formation picture of the Milky Way is suggested, which includes early mergers, collapse, and later accretion.


Globular Cluster Dwarf Galaxy Disk Galaxy Orbital Kinematic Outer Halo 
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Copyright information

© Springer-Verlag New York 2009

Authors and Affiliations

  1. 1.Center for Space AstrophysicsYonsei UniversitySeoul 120-749Korea

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