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Stellar Archaeology: a Keck Pilot Program on Extremely Metal-Poor Stars From the Hamburg/ESO Survey. I Stellar Parameters

Judith G. Cohen·Norbert Christlieb·Timothy C. Beers·Raffaele Gratton·Eugenio Carretta
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Abstract

In this series of two papers we present a high dispersion spectroscopic analysis of 8 candidate extremely metal poor stars selected from the Hamburg/ESO Survey and of 6 additional very metal poor stars. We demonstrate that with suitable vetting using moderate-resolution spectra the yield of this survey for stars with [Fe/H] $\le -3.0$ dex is very high; three out of the eight stars observed thus far at high resolution from the HES are actually that metal poor, three more have [Fe/H] $\le -2.8$ dex, and the remainder are only slightly more metal rich. In preparation for a large scale effort to mine the Hamburg/ESO Survey database for such stars about to get underway, we lay out in this paper the basic principles we intend to use to determine in a uniform way the stellar parameters Teff, surface grav, and reddening.

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Judith G. Cohen, Norbert Christlieb, Timothy C. Beers, Raffaele Gratton, Eugenio Carretta. 2002-04-04. Stellar Archaeology: a Keck Pilot Program on Extremely Metal-Poor Stars From the Hamburg/ESO Survey. I Stellar Parameters. https://doi.org/10.1086/340954

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