The EMBLA survey – metal-poor stars in the Galactic bulge
Name
1604.07834.pdf
Size
5.49 MB
Format
Adobe PDF
Checksum (MD5)
e8dc1ff9d9610fced570e42c39fce8f0
Author(s)
Howes, Louise M.
Asplund, Martin
Keller, Stefan C.
Casey, Andrew R.
Yong, David
Lind, Karin
Frebel, Anna L.
Hays, Austin
Alves-Brito, Alan
Bessell, Michael S.
Date Issued
April 2016
Journal
Monthly Notices of the Royal Astronomical Society
Publisher
Oxford University Press (OUP)
Citation
Howes, Louise M. et al. “The EMBLA Survey – Metal-Poor Stars in the Galactic Bulge.” Monthly Notices of the Royal Astronomical Society 460, 1 (April 2016): 884–901 © 2015 Royal Astronomical Society
Version
Author's final manuscript
Abstract
Cosmological models predict the oldest stars in the Galaxy should be found closest to the centre of the potential well, in the bulge. The Extremely Metal-poor BuLge stars with AAOmega survey (EMBLA) successfully searched for these old, metal-poor stars by making use of the distinctive SkyMapper photometric filters to discover candidate metal-poor stars in the bulge. Their metal-poor nature was then confirmed using the AAOmega spectrograph on the Anglo-Australian Telescope. Here we present an abundance analysis of 10 bulge stars with -2.8 < [Fe/H] < -1.7 from MIKE/Magellan observations, in total determining the abundances of 22 elements. Combining these results with our previous high-resolution data taken as part of the Gaia-ESO Survey, we have started to put together a picture of the chemical and kinematic nature of the most metal-poor stars in the bulge. The currently available kinematic data are consistent with the stars belonging to the bulge, although more accurate measurements are needed to constrain the stars' orbits. The chemistry of these bulge stars deviates from that found in halo stars of the same metallicity. Two notable differences are the absence of carbon-enhanced metal-poor bulge stars, and the alpha element abundances exhibit a large intrinsic scatter and include stars which are underabundant in these typically enhanced elements.
MIT Department
MIT Kavli Institute for Astrophysics and Space Research
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1093/MNRAS/STW1004
