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Related papers: Sulfur abundances in the Galactic bulge and disk

200 papers

The chemical evolution of the Galactic bulge is treated here in the context of an inside-out model for the Galaxy formation. We assume that this central region evolved even faster than the Galactic halo and test the effect of changing the…

Astrophysics · Physics 2007-05-23 F. Matteucci , D. Romano , P. Molaro

The metallicity distribution function (MDF) of the Galactic bulge features a multi-peak shape, with a metal-poor peak at [Fe/H]=-0.3 dex and a metal-rich peak at [Fe/H]=+0.3 dex. This bimodality is also seen in [alpha/Fe] versus [Fe/H]…

Astrophysics of Galaxies · Physics 2024-05-22 M. Molero , F. Matteucci , E. Spitoni , A. Rojas-Arriagada , R. M. Rich

LTE and NLTE abundances of sulfur in 6 metal-poor giants and 61 dwarfs (62 dwarfs, including the Sun) were explored in the range of -3 \lsim [Fe/H] \lsim $+0.5$ using high-resolution, high signal-to-noise ratio spectra of the \SI 8693.9 \AA…

High resolution spectra of 34 halo population dwarf and subgiant stars have been obtained with VLT/UVES and used to derive sulphur abundances from the 8694.0, 8694.6 A and 9212.9, 9237.5 A SI lines. In addition, iron abundances have been…

Astrophysics · Physics 2009-11-10 P. E. Nissen , Y. Q. Chen , M. Asplund , M. Pettini

ABRIDGED: METHODS: We have conducted a high-resolution spectroscopic study of 714 F and G dwarf and subgiant stars in the Solar neighbourhood. The star sample has been kinematically selected to trace the Galactic thin and thick disks to…

Astrophysics of Galaxies · Physics 2015-06-17 T. Bensby , S. Feltzing , M. S. Oey

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 beween the matter ejected and falling back onto…

Astrophysics of Galaxies · Physics 2015-06-17 B. Barbuy , V. Hill , M. Zoccali , D. Minniti , A. Renzini , S. Ortolani , A. Gomez , M. Trevisan , N. Dutra

It is debated whether the Milky Way bulge has the characteristics of a classical bulge sooner than those of a pseudobulge. Detailed abundance studies of bulge stars is a key to investigate the origin, history, and classification of the…

[Abridged abstract] We have performed an abundance analysis for 176 F- and G- dwarfs of the Galactic thick disk component. Using accurate radial velocities combined with $Hipparcos$ astrometry, kinematics (U, V, and W) and Galactic orbital…

Astrophysics · Physics 2009-11-13 Bacham E. Reddy , David L. Lambert , Carlos Allende Prieto

We report on detailed abundances of giants in the Galactic bulge, measured with the HIRES echelle spectrograph on the 10-m Keck telescope. We also review other work on the bulge field population and globular clusters using Keck/HIRES. Our…

Astrophysics · Physics 2015-06-24 R. M. Rich , A. McWilliam

Photospheric abundances are presented for 27 elements from carbon to europium in 181 F-G dwarfs from a differential LTE analysis of high-resolution and high signal-to-noise spectra. Stellar $T_{\rm eff}$ were adopted from an infrared flux…

Astrophysics · Physics 2009-11-07 Bacham E. Reddy , Jocelyn Tomkin , David L. Lambert , Carlos Allende Prieto

We report the first high resolution, detailed abundances of 21 elements for giants in the Galactic bulge/bar within $1^\circ$ of the Galactic plane, where high extinction has rendered such studies challenging. Our high S/N and…

The elemental abundance structure of the Galactic disc has been extensively studied in the solar neighbourhood using long-lived stars such as F and G dwarfs or K and M giants. These are stars whose atmospheres preserve the chemical…

Astrophysics of Galaxies · Physics 2015-05-18 T. Bensby , A. Alves-Brito , M. S. Oey , D. Yong , J. Meléndez

We present detailed abundance results for 9 Galactic bulge stars in Baade's Window, based on HIRES (R=45,000--60,000) spectra taken with the Keck I telescope. The alpha elements show non-uniform enhancements relative to the Solar…

Astrophysics · Physics 2007-05-23 Andrew McWilliam , R. Michael Rich

The galactic bulge is a significant part of our galaxy, but it is hard to observe, being both distant and covered by dust in the disk. Therefore there do not exist many hi-res optical spectra of bulge stars with large wavelength coverage,…

Astrophysics of Galaxies · Physics 2017-02-08 H. Jönsson , N. Ryde , T. Nordlander , A. Pehlivan , H. Hartman , P. Jönsson , K. Eriksson

The structure, formation, and evolution of the Milky Way bulge is a matter of debate. Important diagnostics for discriminating between bulge models include alpha-abundance trends with metallicity, and spatial abundance and metallicity…

Astrophysics of Galaxies · Physics 2015-12-23 N. Ryde , M. Schultheis , V. Grieco , F. Matteucci , R. M. Rich , S. Uttenthaler

We present a high-resolution spectrum of a microlensed G dwarf in the Galactic bulge with spectroscopic temperature T_eff = 5600 +/- 180 K. This I~21 mag star was magnified by a factor ranging from 1160 to 1300 at the time of observation.…

Solar and Stellar Astrophysics · Physics 2014-11-20 Courtney R. Epstein , Jennifer A. Johnson , Subo Dong , Andrzej Udalski , Andrew Gould , George Becker

We present a comprehensive chemical abundance analysis of five red giants and two horizontal branch (HB) stars towards the southern Galactic bulge, at (l,b)$\sim$(0$^{\rm o}$,-11$^{\rm o}$). Based on high-resolution spectroscopy obtained…

Astrophysics of Galaxies · Physics 2016-03-16 Andreas Koch , Andrew McWilliam , George W. Preston , Ian B. Thompson

We analyze a high-resolution spectrum of a microlensed G-dwarf in the Galactic bulge, acquired when the star was magnified by a factor of 110. We measure a spectroscopic temperature, derived from the wings of the Balmer lines, that is the…

Astrophysics · Physics 2009-11-13 Jennifer A. Johnson , B. Scott Gaudi , Takahiro Sumi , Ian A. Bond , Andrew Gould

AIMS: We spectroscopically characterize the Galactic Bulge to infer its star formation timescale, compared to the other Galactic components, through the chemical signature on its individual stars. METHODS: We derived iron and oxygen…

Astrophysics · Physics 2010-01-07 M. Zoccali , A. Lecureur , B. Barbuy , V. Hill , A. Renzini , D. Minniti , Y. Momany , A. Gomez , S. Ortolani

Zinc in stars is an important reference element because it is a proxy to Fe in studies of damped Lyman-alpha systems, permitting a comparison of chemical evolution histories of bulge stellar populations and DLAs. In terms of…

Astrophysics of Galaxies · Physics 2015-07-29 B. Barbuy , A. C. S. Friaca , C. R. da Silveira , V. Hill , M. Zoccali , D. Minniti , A. Renzini , S. Ortolani , A. Gomez