dc.contributor.author | Johnson, Christian I. | |
dc.contributor.author | Rich, R. Michael | |
dc.contributor.author | Kobayashi, Chiaki | |
dc.contributor.author | Kunder, Andrea | |
dc.contributor.author | Koch, Andreas | |
dc.date.accessioned | 2017-07-20T16:04:24Z | |
dc.date.available | 2017-07-20T16:04:24Z | |
dc.date.issued | 2014-09-09 | |
dc.identifier.citation | Johnson , C I , Rich , R M , Kobayashi , C , Kunder , A & Koch , A 2014 , ' Light, Alpha, and Fe-Peak Element Abundances in the Galactic Bulge ' , The Astronomical Journal , vol. 148 , no. 4 , 67 . https://doi.org/10.1088/0004-6256/148/4/67 | |
dc.identifier.issn | 0004-6256 | |
dc.identifier.other | ArXiv: http://arxiv.org/abs/1407.2282v1 | |
dc.identifier.other | ORCID: /0000-0002-4343-0487/work/62750444 | |
dc.identifier.uri | http://hdl.handle.net/2299/19021 | |
dc.description | C. I. Johnson, et al., “Light, Alpha, and Fe-Peak Element Abundances in the Galactic Bulge”, The Astronomical Journal, Vol. 148(4), September 2014. This version of record is available online at: http://iopscience.iop.org/article/10.1088/0004-6256/148/4/67/meta © 2014. The American Astronomical Society. All rights reserved. Printed in the U.S.A | |
dc.description.abstract | We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l,b)=(+5.25,-3.02) and (0,-12). The (+5.25,-3.02) field also includes observations of the bulge globular cluster NGC 6553. The results are based on high resolution (R~20,000), high signal-to-noise (S/N>70) FLAMES-GIRAFFE spectra obtained through the ESO archive. However, we only selected a subset of the original observations that included spectra with both high S/N and that did not show strong TiO absorption bands. The present work extends previous analyses of this data set beyond Fe and the alpha-elements Mg, Si, Ca, and Ti. While we find reasonable agreement with past work, the data presented here indicate that the bulge may exhibit a different chemical composition than the local thick disk, especially at [Fe/H]>-0.5. In particular, the bulge [alpha/Fe] ratios may remain enhanced to a slightly higher [Fe/H] than the thick disk and the Fe-peak elements Co, Ni, and Cu appear enhanced compared to the disk. There is also some evidence that the [Na/Fe] (but not [Al/Fe]) trends between the bulge and local disk may be different at low and high metallicity. We also find that the velocity dispersion decreases as a function of increasing [Fe/H] for both fields, and do not detect any significant cold, high velocity population. A comparison with chemical enrichment models indicates that a significant fraction of hypernovae are required to explain the bulge abundance trends, and that initial mass functions that are steep, top-heavy (and do not include strong outflow), or truncated to avoid including contributions from stars >40 solar masses are ruled out, in particular because of disagreement with the Fe-peak abundance data. [abridged] | en |
dc.format.extent | 32 | |
dc.format.extent | 4193683 | |
dc.language.iso | eng | |
dc.relation.ispartof | The Astronomical Journal | |
dc.subject | astro-ph.SR | |
dc.subject | astro-ph.GA | |
dc.title | Light, Alpha, and Fe-Peak Element Abundances in the Galactic Bulge | en |
dc.contributor.institution | School of Physics, Astronomy and Mathematics | |
dc.contributor.institution | Science & Technology Research Institute | |
dc.contributor.institution | Centre for Astrophysics Research | |
dc.description.status | Peer reviewed | |
rioxxterms.versionofrecord | 10.1088/0004-6256/148/4/67 | |
rioxxterms.type | Journal Article/Review | |
herts.preservation.rarelyaccessed | true | |