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Tracing the Galactic thick disk to Solar metallicities

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 نشر من قبل Thomas Bensby
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف T. Bensby




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We show that the Galactic thick disk reaches at least solar metallicities, and that it experienced strong chemical enrichment during a period of ~3 Gyr, ending around 8-9 Gyr ago. This finding puts further constraints on the relation and interface between the thin and thick disks, and their formation processes. Our results are based on a detailed elemental abundance analysis of 261 kinematically selected F and G dwarf stars in the solar neighborhood: 194 likely members of the thick disk and 67 likely members of the thin disk, in the range -1.3<[Fe/H]<+0.4.

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