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Bright Metal-Poor Stars from the Hamburg/ESO Survey. I. Selection and Follow-up Observations from 329 Fields

A. Frebel·N. Christlieb·J. E. Norris·T. C. Beers·M. S. Bessell·J. Rhee·C. Fechner·B. Marsteller·S. Rossi·C. Thom·L. Wisotzki·D. Reimers
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Abstract

We present a sample of 1777 bright (9 1.0) metal-poor ([Fe/H]<-2.0) giants of 9% +- 2%, which is lower than previously reported. However, the frequency raises to similar (>20%) and higher values with increasing distance from the Galactic plane. Although the numbers of stars at low metallicity are falling rapidly at the lowest metallicities, there is evidence that the fraction of carbon-enhanced metal-poor stars is increasing rapidly as a function of declining metallicity. For ~60 objects, high-resolution data have already been obtained; one of these, HE 1327-2326, is the new record holder for the most iron-deficient star known.

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A. Frebel, N. Christlieb, J. E. Norris, T. C. Beers, M. S. Bessell, J. Rhee, C. Fechner, B. Marsteller, S. Rossi, C. Thom, L. Wisotzki, D. Reimers. 2006-08-16. Bright Metal-Poor Stars from the Hamburg/ESO Survey. I. Selection and Follow-up Observations from 329 Fields. https://doi.org/10.1086/508506

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