Stellar Archaeology: A Keck Pilot Program on Extremely Metal-poor Stars from the Hamburg/ESO Survey. I. Stellar Parameters

In this series of two papers we present a high dispersion spectroscopicanalysis of 8 candidate extremely metal poor stars selected from theHamburg/ESO Survey and of 6 additional very metal poor stars. We demonstratethat with suitable vetting using moderate-resolution spectra the yield of thissurvey for stars with [Fe/H] $\le -3.0$ dex is very high; three out of theeight stars observed thus far at high resolution from the HES are actually thatmetal poor, three more have [Fe/H] $\le -2.8$ dex, and the remainder are onlyslightly more metal rich. In preparation for a large scale effort to mine theHamburg/ESO Survey database for such stars about to get underway, we lay out inthis paper the basic principles we intend to use to determine in a uniform waythe stellar parameters Teff, surface grav, and reddening.Comment: The first in a set of two papers, accepted for publication by the A