Discovery of HE 1523–0901, a Strongly r-Process-enhanced Metal-poor Star with Detected Uranium

  title={Discovery of HE 1523–0901, a Strongly r-Process-enhanced Metal-poor Star with Detected Uranium},
  author={Anna Frebel and Norbert Christlieb and John E. Norris and Christopher Thom and Timothy C. Beers and Jaehyon Rhee},
  journal={The Astrophysical Journal Letters},
  pages={L117 - L120}
We present age estimates for the newly discovered, very r-process-enhanced metal-poor star HE 1523-0901 ([Fe/H] = -2.95) based on the radioactive decay of Th and U. The bright (V = 11.1) giant was found among a sample of bright metal-poor stars selected from the Hamburg/ESO Survey. From an abundance analysis of a high-resolution (R = 75,000) VLT/UVES spectrum, we find HE 1523-0901 to be strongly overabundant in r-process elements ([r/Fe] = 1.8). The abundances of heavy neutron-capture elements… 

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