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Title: Metal-poor Stars Observed with the Southern African Large Telescope II. An Extended Sample
Abstract

We present results from high-resolution (R∼ 40,000) spectroscopic observations of over 200 metal-poor stars, mostly selected from the RAVE survey, using the Southern African Large Telescope. We were able to derive stellar parameters for a total of 108 stars; an additional sample of 50 stars from this same effort was previously reported on by Rasmussen et al. Among our newly reported observations, we identify 84 very metal-poor (VMP; [Fe/H] < −2.0, 53 newly identified) stars and three extremely metal-poor (EMP; [Fe/H] < −3.0, one newly identified) stars. The elemental abundances were measured for carbon, as well as several otherα-elements (Mg, Ca, Sc, and Ti), iron-peak elements (Mn, Co, Ni, and Zn), and neutron-capture elements (Sr, Ba, and Eu). Based on these measurements, the stars are classified by their carbon and neutron-capture abundances into carbon-enhanced metal-poor (CEMP; [C/Fe] > +0.70), CEMP subclasses, and by the level of theirr-process abundances. A total of 17 are classified as CEMP stars. There are 11 CEMP-rstars (eight newly identified), one CEMP-sstar (newly identified), two possible CEMP-istars (one newly identified), and three CEMP-no stars (all newly identified) in this work. We found 11 stars (eight newly identified) that are strongly enhanced inr-process elements (r-II; [Eu/Fe] > +0.70), 38 stars (31 newly identified) that are moderately enhanced inr-process elements (r-I; +0.30 < [Eu/Fe] ≤ + 0.70), and one newly identified limited-rstar.

 
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NSF-PAR ID:
10363669
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
927
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 13
Size(s):
Article No. 13
Sponsoring Org:
National Science Foundation
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