Most metal-poor stars. III. 86 [Fe/H]<=-3.0 stars

DOI

We examine the metallicity distribution function (MDF) and fraction of carbon-enhanced metal-poor (CEMP) stars in a sample that includes 86 stars with [Fe/H]<=-3.0, based on high-resolution, high signal-to-noise spectroscopy, of which some 32 objects lie below [Fe/H]=-3.5. After accounting for the completeness function, the "corrected" MDF does not exhibit the sudden drop at [Fe/H]=-3.6 that was found in recent samples of dwarfs and giants from the Hamburg/ESO survey. Rather, the MDF decreases smoothly down to [Fe/H]=-4.1. Similar results are obtained from the "raw" MDF. We find that the fraction of CEMP objects below [Fe/H]=-3.0 is 23%+/-6% and 32%+/-8% when adopting the Beers & Christlieb (2005ARA&A..43..531B) and Aoki et al. (2007, J/ApJ/655/492) CEMP definitions, respectively. The former value is in fair agreement with some previous measurements, which adopt the Beers & Christlieb criterion.

Cone search capability for table J/ApJ/762/27/table1 (Stellar parameters and carbon abundance)

Identifier
DOI http://doi.org/10.26093/cds/vizier.17620027
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/762/27
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/762/27
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/762/27
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/762/27
Provenance
Creator Yong D.; Norris J.E.; Bessell M.S.; Christlieb N.; Asplund M.; Beers T.C.,Barklem P.S.; Frebel A.; Ryan S.G.
Publisher CDS
Publication Year 2014
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Galactic and extragalactic Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy