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The age of the Galaxys thick disk

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 نشر من قبل Thomas Bensby
 تاريخ النشر 2008
  مجال البحث فيزياء
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We discuss the age of the stellar disks in the solar neighbourhood. After reviewing the various methods for age dating we discuss current estimates of the age of both the thin and the thick disk. We present preliminary results for kinematically-selected stars that belong to the thin as well as the thick disk. All of these dwarf and sub-giant stars have been studied spectroscopically and we have derived both elemental abundances as well as ages for them. A general conclusion is that in the solar neighbourhood, on average, the thick disk is older than the thin disk. However, we caution that the exclusion of stars with effective temperatures around 6500 K might result in a biased view on the full age distribution for the stars in the thick disk.

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