Structure and Dynamics of the Old Galactic Components

  • Masashi Chiba
  • Hirohito Hayashi
  • Motoko Yamada
Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP)

We present here the recent progress in our understanding of the old stellar components of the Milky Way as fossil records of galaxy formation. Special attention will be paid to if the Cold Dark Matter (CDM) theory as a current theoretical paradigm is able to reproduce recently accumulated data sets of Galactic stars as provided by extensive surveys such as SDSS. We show our recent studies in this regard. First, we have simulated the dynamical interaction between a stellar disk and numerous CDM subhalos to get insights into the origin of the thin and thick disks. Second, we have analyzed the global dynamics of more than 1600 field horizontal branch stars as halo tracers to probe their velocity distribution inside the dark halo of the Milky Way. A detailed comparison with the CDM predictions has been made and key issues are addressed for understanding the formation of the Milky Way.


Cold Dark Matter Thin Disk Thick Disk Stellar Disk Galaxy Formation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Masashi Chiba
    • 1
  • Hirohito Hayashi
    • 1
  • Motoko Yamada
    • 1
  1. 1.Astronomical InstituteTohoku UniversityJapan

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