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A stellar relic from the early Milky Way
This work reports the discovery of a low-mass star with an iron abundance as low as 1/200,000 of the solar value, which suggests that population III stars could still exist and that the first generation of stars also contained long-livedLow-mass objects.
The Hamburg/ESO R-process enhanced star survey (HERES). II. Spectroscopic analysis of the survey sample
We present the results of analysis of "snapshot" spectra of 253 metal-poor halo stars −3.8 ≤ (Fe/H) ≤− 1.5 obtained in the HERES survey. The snapshot spectra have been obtained with VLT/UVES and have
Kinematics of Metal-poor Stars in the Galaxy. II. Proper Motions for a Large Nonkinematically Selected Sample
We present a revised catalog of 2106 Galactic stars, selected without kinematic bias and with available radial velocities, distance estimates, and metal abundances in the range -4.0 ≤ [Fe/H] ≤ 0.0.
The Frequency of Carbon-enhanced Metal-poor Stars in the Galaxy from the HERES Sample
We estimate the frequency of carbon-enhanced metal-poor (CEMP) stars among very metal-poor stars, based on an analysis of 349 stars with available high-resolution spectra observed as part of the
Bright Metal-poor Stars from the Hamburg/ESO Survey. I. Selection and Follow-up Observations from 329 Fields
We present a sample of 1777 bright (9 1.0) metal-poor ([Fe/H] 20%) and higher values with increasing distance from the Galactic plane. Although the numbers of stars at low metallicity are falling
Estimation of Stellar Metal Abundance. II. A Recalibration of the Ca II K Technique, and the Autocorrelation Function Method
We have recalibrated a method for the estimation of stellar metal abundance, parameterized as [Fe/H], based on medium-resolution (1–2 A) optical spectra (the majority of which cover the wavelength
Elemental abundances and classification of carbon-enhanced metal-poor stars
We present a detailed study of carbon-enhanced metal-poor (CEMP) stars, based on high-resolution spectroscopic observations of a sample of 18 stars. The stellar spectra for this sample were obtained
Metal Abundances and Kinematics of Bright Metal-poor Giants Selected from the LSE Survey: Implications for the Metal-weak Thick Disk
We report medium-resolution (1–2 A) spectroscopy and broadband (UBV) photometry for a sample of 39 bright stars (the majority of which are likely to be giants) selected as metal-deficient candidates
The Near-Infrared Na I Doublet Feature in M Stars*
The Na I near-infrared feature has been used to indicate the dwarf/giant population in composite systems, but its interpretation is still an issue of contention. In order to try to understand the
The Hamburg/ESO R-process Enhanced Star survey (HERES). I. Project description, and discovery of two stars with strong enhancements of neutron-capture elements
We report on a dedicated effort to identify and study metal-poor stars strongly enhanced in r-process elements ((r/Fe) > 1 dex; hereafter r-II stars), the Hamburg/ESO R-process Enhanced Star survey