Surprising Metallicity of a Newly Discovered M79 Post-AGB Star

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Şahin T., Lambert D.

New Horizons in Astronomy: Frank N. Bash Symposium 2009 (ISBN: 978-1-58381-744-5 ), Texas, Amerika Birleşik Devletleri, 18 - 20 Ekim 2009, cilt.432, ss.254-258, (Tam Metin Bildiri)

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası: 432
  • Basıldığı Şehir: Texas
  • Basıldığı Ülke: Amerika Birleşik Devletleri
  • Sayfa Sayıları: ss.254-258
  • Akdeniz Üniversitesi Adresli: Hayır

Özet


A detailed chemical composition analysis based on a high-resolution (R≍35,000) CCD spectrum is presented for a newly discovered post-AGB star in the globular cluster M79 for the first time. The elemental abundance results of M79 post-AGB star are found to be [C/Fe] ≍ -0.7, [O/Fe] = +1.4, [α-process/Fe] ≍ 0.5, and [s-process/Fe] ≍ -0.1. The surprising result is that the iron abundance of the star is apparently about 0.6 dex less than that of the cluster’s red giants as reported by published studies including a recent high-resolution spectroscopic analysis by Carretta and colleagues.