Abundances in two Galactic bulge stars

DOI

We present abundance analyses based on high dispersion and high signal-to-noise ratio Magellan spectra of two highly microlensed Galactic bulge stars in the region of the main-sequence turnoff with T_eff_~5650K. We find that MOA-2008-BLG-310S has [Fe/H]^8^=+0.41+/-0.09dex and MOA-2008-BLG-311S has +0.26+/-0.09dex. The abundance ratios for the ~20 elements for which features could be detected in the spectra of each of the two stars follow the trends with [Fe/H] found among samples of bulge giants. Combining these two bulge dwarfs with the results from previous abundance analysis of four other Galactic bulge turnoff region stars, all highly magnified by microlensing, gives a mean [Fe/H] of +0.29dex. This implies that there is an inconsistency between the Fe-metallicity distribution of the microlensed bulge dwarfs and that derived by the many previous estimates based on surveys of cool, luminous bulge giants, which have mean [Fe/H]~-0.1dex.

Identifier
DOI http://doi.org/10.26093/cds/vizier.16990066
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/699/66
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/699/66
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/699/66
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/699/66
Provenance
Creator Cohen J.G.; Thompson I.B.; Sumi T.; Bond I.; Gould A.; Johnson J.A.,Huang W.; Burley G.
Publisher CDS
Publication Year 2011
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 Astrophysical Processes; Astrophysics and Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy