Advanced search
Start date
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Manganese abundances in Galactic bulge red giants

Full text
Barbuy, B. [1] ; Hill, V. [2] ; Zoccali, M. [3] ; Minniti, D. [3, 4] ; Renzini, A. [5] ; Ortolani, S. [6] ; Gomez, A. [7] ; Trevisan, M. [8] ; Dutra, N. [1]
Total Authors: 9
[1] Univ Sao Paulo, IAG, BR-05508900 Sao Paulo - Brazil
[2] Univ Sophia Antipolis, CNRS, Observ Cote Azur, Lab Lagrange, F-06304 Nice 4 - France
[3] Pontificia Univ Catolica Chile, Fac Fis, Inst Astrofis, Santiago 22 - Chile
[4] Vatican Observ, I-00120 Vatican City - Vatican
[5] Osserv Astron Padova, I-35122 Padua - Italy
[6] Univ Padua, Dipartimento Astron, I-35122 Padua - Italy
[7] Observ Paris, F-92195 Meudon - France
[8] Inst Nacl Pesquisas Espaciais, BR-12227010 Sao Jose Dos Campos - Brazil
Total Affiliations: 8
Document type: Journal article
Source: Astronomy & Astrophysics; v. 559, NOV 2013.
Web of Science Citations: 20

Context. Manganese is mainly produced in type II SNe during explosive silicon burning, in incomplete Si-burning regions, and depends on several nucleosynthesis environment conditions, such as mass cut between the matter ejected and falling back onto the remnant, electron and neutron excesses, mixing fallback, and explosion energy. Manganese is also produced in type Ia SNe. Aims. The aim of this work is the study of abundances of the iron-peak element Mn in 56 bulge giants, among which 13 are red clump stars. Four bulge fields along the minor axis are inspected. The study of abundances of Mn-over-Fe as a function of metallicity in the Galactic bulge may shed light on its production mechanisms. Methods. High-resolution spectra were obtained using the FLAMES+ UVES spectrograph on the Very Large Telescope. The spectra were obtained within a program to observe 800 stars using the GIRAFFE spectrograph, together with the present UVES spectra. Results. We aim at identifying the chemical evolution of manganese, as a function of metallicity, in the Galactic bulge. We find {[}Mn/Fe] similar to -0.7 at {[}Fe/H] similar to -1.3, increasing to a solar value at metallicities close to solar, and showing a spread around -0.7 less than or similar to {[}Fe/H] less than or similar to -0.2, in good agreement with other work on Mn in bulge stars. There is also good agreement with chemical evolution models. We find no clear difference in the behaviour of the four bulge fields. Whereas {[}Mn/Fe] vs. {[}Fe/H] could be identified with the behaviour of the thick disc stars, {[}Mn/O] vs. {[}O/H] has a behaviour running parallel, at higher metallicities, compared to thick disc stars, indicating that the bulge enrichment might have proceeded differently from that of the thick disc. (AU)

FAPESP's process: 12/05142-5 - Assembling Baryons to Dark Halos: Stellar Content and the Star Formation History of Early-­type Galaxies
Grantee:Marina Trevisan
Support type: Scholarships in Brazil - Post-Doctorate